Green Bean Casserole with Pretzel Bun Breadcrumb Topping
This Creamy Green Bean & Mushroom Casserole with Pretzel Breadcrumb and Crispy Onion Topping is the ultimate twist on a classic, traditional green bean casserole. Tender green beans and earthy mushrooms come together in a rich, savory sauce, topped with a crunchy, golden layer of coarse pretzel breadcrumbs and crispy, buttermilk-soaked onions. You get a ton of flavor by combining basic ingredients. This will be one of the Thanksgiving sides you will make again and again.
Whether you’re looking for a new Thanksgiving Dinner, the perfect side dish on the holiday table, or a comforting dinner for any night, this homemade Green Bean Casserole recipe delivers both flavor and texture in every bite. The unique pretzel bun topping ties it all together with rustic charm, elevating one of the easy casserole recipes we all love into a complete standout!
Why you will love this recipe
Rich and creamy – the combination of sautéed leeks and mushrooms in a creamy sauce creates a rich and satisfying base that complements the freshness of the green beans.
Delicious textures – the crispy onion topping and coarse pretzel breadcrumbs add a wonderful crunch that contrasts beautifully with the creamy filling, making every bite an exciting experience.
Versatile dish – This casserole is versatile. You can serve it as a holiday side or a weeknight meal.
Easy to make – with straightforward steps and common ingredients, this casserole is simple to prepare.
Ingredients, Variations and Substitutions
Fresh Green Beans – crisp and tender, green beans provide a fresh, vibrant flavor and a satisfying crunch. Look for bright green beans with a firm texture; avoid those that are limp or yellowing. Frozen green beans can be used if fresh ones are unavailable; just blanch them briefly before adding to the casserole.
Cremini or button mushrooms – add an earthy flavor and a meaty texture to the casserole, enhancing its richness. Clean mushrooms gently with a damp cloth; avoid soaking them in water, as they absorb moisture. Shiitake or portobello mushrooms can be used for a deeper flavor, but adjust the cooking time accordingly.
Leeks – offer a mild, slightly sweet onion flavor that complements the other ingredients beautifully. Use only the white and light green parts, and wash them thoroughly to remove any grit. Shallots or sweet onions, or even red onions can be used if leeks are unavailable, though the flavor profile will differ slightly.
Vegetable or chicken broth – adds moisture and flavor to the sauce, enhancing the dish’s savory profile. Choose low-sodium broth to control the dish’s saltiness. If broth is unavailable, homemade broth or water with bouillon cubes can be used.
Garlic – Garlic adds depth and aroma, enhancing the overall flavor of the dish. Fresh garlic is preferred for the best flavor; adjust the amount based on your taste. Garlic powder can be used in a pinch (1/2 teaspoon = 1 clove), but fresh garlic is recommended for maximum flavor.
Heavy Cream – provides a rich, creamy texture to the sauce. You can substitute half-and-half or whole milk for a lighter version, though the sauce may be less thick. Coconut milk or cream can be used as a dairy-free option, but it will impart a coconut flavor.
Unsalted Butter – adds richness and flavor to the sauce while helping to sauté the leeks and mushrooms. Use unsalted butter to better control the dish’s overall salt content. Olive oil or dairy-free butter can be used as alternatives.
Flour – helps thicken the sauce, giving it a creamy consistency that clings to the green beans. Ensure it’s cooked briefly to eliminate the raw taste. Gluten-free flour or cornstarch (1 tbsp mixed with water) can be a thickener for gluten-free options.
Parmesan Cheese or Gruyere Cheese – adds a savory depth and enhances the creaminess of the dish. Freshly grated cheese melts better than pre-grated varieties. Other cheeses like cheddar, asiago cheese or mozzarella can work, though flavors will differ.
Pretzel Bun Breadcrumbs – they add a crunchy, salty topping that enhances the casserole’s texture. Make sure they’re coarse to achieve the desired crunch. Panko breadcrumbs, crushed corn flakes or crushed potato chips can be used, but season them with a bit of salt and garlic powder for a similar flavor.
Salt and Black Pepper – essential for seasoning the dish and enhancing all the flavors. Adjust to your taste preferences. Garlic salt or onion powder can add a different flavor profile if desired.
Nutmeg – adds warmth and complexity to the flavor of the sauce. Use freshly grated nutmeg for the best flavor. Cinnamon or allspice can work but use sparingly as they have distinct flavors.
Thyme – adds an aromatic herbaceous note to the casserole. Fresh thyme has a brighter flavor, while dried thyme is more concentrated. Other herbs like rosemary or oregano can be used but will change the flavor profile.
For the crispy onions:
Yellow onion – thinly sliced into half moons. If you prefer a milder flavor, substitute it with a sweet Vidalia onion or even shallots.
Buttermilk – helps to tenderize the onions and adds a slight tanginess. If you don’t have it on hand, mix regular milk with a tablespoon of lemon juice or vinegar, which creates a similar acidic effect.
Flour and pretzel bun breadcrumbs – used to coat the onions for a crispy texture. You can also use panko breadcrumbs or gluten-free breadcrumbs.
Cornstarch – is optional but highly recommended for achieving that extra crispness that stays crunchy even after frying.
Salt, black pepper, and garlic powder – add them to the coating. You can experiment with other seasonings based on your preference.
Vegetable oil – for frying the onions. It works best as it has a neutral flavor and high smoke point, but you can also use canola or peanut oil if preferred. Make sure the oil is hot enough to get the onions crispy and golden.
Equipment you will need
- Large Pot
- Colander
- Large Skillet
- Whisk
- Spatula or Wooden Spoon
- Oven-Safe Baking Dish (9×13-inch recommended)
- Mixing Bowl
- Baking Sheet, paper towels
- Spider strainer or slotted spoon
- Sharp Knife and Cutting Board
- Measuring Cups and Spoons
Top Tips
Blanch green beans properly – blanching the green beans in boiling water for just a few minutes helps them retain their vibrant color and crisp texture. Immediately transfer them to an ice bath to stop the cooking process.
Sauté thoroughly – cook the leeks and mushrooms until nicely softened and browned. This enhances their flavors and prevents the casserole from being watery.
Cook the flour – add the flour to the skillet and cook it for about a minute to eliminate the raw flour taste. Stir continuously to avoid clumping.
Whisk slowly – gradually add broth and cream while whisking constantly. This helps prevent lumps in your sauce and creates a smooth texture.
Crispy topping – Mix the pretzel breadcrumbs with a bit of melted butter or olive oil before sprinkling them on the casserole for an extra crunchy topping. This helps them crisp up nicely in the oven.
Add cheese wisely – If using cheese, consider mixing some into the sauce and saving a portion for the topping to create a gooey, cheesy interior with a crispy finish.
Watch the baking time – keep an eye on the casserole as it bakes. If the top is browning too quickly, cover it with foil to prevent burning while allowing the inside to heat through.
Step-by-step instructions
- Place the sliced onions in a bowl and cover them with buttermilk. Let them soak for at least 20 minutes (up to 1 hour for extra tenderness).
- Mix the flour, breadcrumbs, cornstarch, garlic powder, salt, and pepper in a separate bowl.
- Remove the onions from the buttermilk, letting the excess drip off, and dredge them in the flour-breadcrumb mixture until well coated.
- Heat about 1/2 inch of oil in a skillet over medium-high heat. Fry the onions until they become golden brown and crispy, about 2-3 minutes per batch.
- Drain on paper towels and set aside to use as the topping later on.
- Bring a large pot of salted water to a boil.
- Blanch the green beans in salted boiling water for 3-4 minutes, then transfer to an ice bath. Drain and set aside.
- In a large skillet, melt the butter over medium heat. Add the leeks and cook until softened, about 5 minutes. Add the mushrooms and garlic, sautéing until mushrooms are golden, about 5-6 minutes.
- Stir the flour into the cooked leeks and mushrooms, and cook for 1 minute. Slowly whisk in the broth and heavy cream. Simmer for 5 minutes until thickened. Add nutmeg, thyme, salt, and pepper to taste.
- Combine the green beans with the mushroom-leek sauce and mix well. Transfer to a casserole dish. Top with grated cheese.
- Sprinkle the pretzel bun breadcrumbs evenly over the cheese layer and finish with crispy onions.
- Place the casserole dish in the oven set at 375°F (190°C). Bake the casserole for 15-20 minutes until bubbly and golden.
How to best enjoy this Green Bean Casserole
Pair with protein – this casserole is a fantastic side dish for various main courses. It complements roasted turkey, glazed ham, or a savory pot roast.
Garnish – add a sprinkle of freshly chopped herbs (like parsley or thyme) right before serving for a pop of color and added freshness. A squeeze of lemon juice can also brighten the flavors.
Make it a full meal – serve the casserole alongside a light salad, wild rice/brown rice (or any kind of rice), or a warm white bread roll to create a comforting, hearty meal. A simple mixed greens salad with a tangy vinaigrette works wonderfully to balance the richness of the casserole.
Experiment with add-ons – enjoy the dish as is, or feel free to experiment by adding your favorite ingredients. Try adding cooked bacon, chicken breast, or pancetta for a smoky flavor or different veggies like broccoli or cauliflower for variety. Do you want a unique twist? Try adding puff pastry on top of the casserole. You can also add roasted sweet potatoes to make your casserole more colorful and full of flavor!
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Storage Instructions
- Allow the casserole to cool to room temperature before storing it. This prevents condensation from forming inside the container, which can make the casserole soggy.
- Transfer any leftovers to an airtight container or cover the baking dish tightly with plastic wrap or aluminum foil to keep it fresh.
- Store the casserole in the refrigerator if you plan to eat it within 3-4 days.
- If you want to keep the casserole for a longer period, you can freeze it. Place the cooled casserole in a freezer-safe container or wrap it tightly in aluminum foil and plastic wrap. It can be frozen for up to 2-3 months.
Reheating Instructions
- Reheating from the Refrigerator:
- Oven Method: Preheat your oven to 350°F (175°C). Remove the cover from the casserole and place it in the oven. Heat for about 20-25 minutes or until warmed through. If the topping starts to brown too much, cover it with foil during reheating.
- Microwave Method: For quick reheating, place a serving in a microwave-safe dish. Cover it loosely with a microwave-safe lid or paper towel to prevent splatters. Heat in 30-second intervals, stirring in between, until warmed through.
- Reheating from Frozen:
- If you’ve frozen the casserole, it’s best to thaw it in the refrigerator overnight before reheating.
- Oven Method: Preheat your oven to 350°F (175°C). Cover the casserole with foil and bake for about 30-40 minutes, or until heated through. Remove the foil for the last 10 minutes to crisp the topping.
- Microwave Method: If you need to reheat from frozen, you can microwave it on low power, but this may not yield the best results. It’s better to thaw it overnight first.
Best Green Bean and Mushroom Casserole with Breadcrumbs and Crispy Onions
Equipment
- large pot
- colander
- large skillet
- whisk
- spatula or wooden spoon
- oven safe baking dish
- mixing bowl
- sharp knife and cutting board
- measuring cups and spoons
- baking sheet, paper towels
- spider strainer
Ingredients
For the Casserole
- 1 lb fresh green beans
- 8 oz cremini or button mushrooms
- 1-2 leeks
- 2 cloves garlic
- 1 cup vegetable or chicken broth
- 1 cup heavy cream
- 2 tbsp unsalted butter
- 2 tbsp flour
- 1/2 cup grated parmesan or gruyere cheese
- 1/2 cup pretzel bun breadcrumbs
- Salt and pepper
- 1/4 tsp ground nutmeg
- 1/4 tsp thyme
For the Crispy Onions
- 1 large yellow onion thinly sliced
- 1 cup buttermilk
- 1/2 cup flour
- 1/2 cup breadcrumbs
- 1/4 cup cornstarch
- 1/2 tsp garlic powder
- Salt and pepper
- Vegetable oil
Instructions
- Place the sliced onions in a bowl and cover them with buttermilk. Let them soak for at least 20 minutes (up to 1 hour for extra tenderness).
- Mix the flour, breadcrumbs, cornstarch, garlic powder, salt, and pepper in a separate bowl.
- Remove the onions from the buttermilk, letting the excess drip off, and dredge them in the flour-breadcrumb mixture until well coated.
- Heat about 1/2 inch of oil in a skillet over medium-high heat. Fry the onions until they become golden brown and crispy, about 2-3 minutes per batch.
- Drain on paper towels and set aside to use as the topping later on.
- Bring a large pot of salted water to a boil.
- Blanch the green beans in salted boiling water for 3-4 minutes, then transfer to an ice bath. Drain and set aside.
- In a large skillet, melt the butter over medium heat. Add the leeks and cook until softened, about 5 minutes. Add the mushrooms and garlic, sautéing until mushrooms are golden, about 5-6 minutes.
- Stir the flour into the cooked leeks and mushrooms, and cook for 1 minute. Slowly whisk in the broth and heavy cream. Simmer for 5 minutes until thickened. Add nutmeg, thyme, salt, and pepper to taste.
- Combine the green beans with the mushroom-leek sauce and mix well. Transfer to a casserole dish. Top with grated cheese.
- Sprinkle the pretzel bun breadcrumbs evenly over the cheese layer and finish with crispy onions.
- Place the casserole dish in the oven set at 375°F (190°C). Bake the casserole for 15-20 minutes until bubbly and golden.
Notes
Nutrition
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Conclusion
This Creamy Green Bean & Mushroom Casserole is a delightful twist on a classic favorite, bringing together fresh green beans, earthy mushrooms, and the irresistible crunch of pretzel bun breadcrumbs and crispy onions.
Whether served at a festive holiday gathering or as a comforting side for a weeknight meal, this dish promises to be a hit at your table. With its rich flavors and satisfying textures, it’s not just a side dish—it’s a standout that will have everyone asking for seconds. So gather your ingredients, follow the recipe, and enjoy the warmth and joy this easy green bean casserole brings to your home which is guaranteed to be one of your new favorite comfort food!
Happy cooking!
FAQ
Can I make this Green Bean Casserole ahead of time?
Yes! You can prepare the casserole a day in advance. Assemble the ingredients and cover the dish tightly. Store it in the refrigerator and bake it just before serving. If it goes in the oven cold, you may need to add a few extra minutes to the baking time.
What can I substitute for green beans?
If you don’t have green beans, you can use fresh or frozen broccoli, asparagus, or cauliflower. Adjust the cooking time as needed for each vegetable.
Can I make this dish vegetarian?
Yes! This casserole is already vegetarian. Ensure that your vegetable broth is also vegetarian or vegan to maintain the dish’s status.
How can I make the casserole gluten-free?
To make this dish gluten-free, use gluten-free flour and breadcrumbs, and ensure that the broth is also gluten-free.
Can I add other ingredients to the casserole?
Definitely! Feel free to get creative by adding cooked chicken, bacon, or vegetables like bell peppers or corn to enhance the dish.
Can I use other types of cheese in this recipe?
Yes! If you’d like to add cheese, try using shredded cheddar, Gruyère, or mozzarella for extra creaminess and flavor.
How can I enhance the flavor of the sauce?
You can enhance the sauce’s flavor by adding soy sauce, Worcestershire sauce, or fresh herbs like rosemary or thyme. A dash of hot sauce can also add a nice kick! But if you’re looking for added creaminess, you can add sour cream or a few tablespoons of softened cream cheese.
