Spread ½ cup hazelnuts on a tray and toast at 350°F for 8–10 minutes until fragrant. Let cool; rub in a towel to remove skins if you like (optional).
Pulse cooled hazelnuts in a food processor to a fine meal (don’t over-process into paste). Set aside.
In a large bowl, whisk together: 1 ¼ cups all-purpose flour, 2 tbsp ground flaxseed, 1 tbsp granulated sugar, ½ tsp salt.
Cut in ½ cup (1 stick) cold butter, cubed, until mixture looks like coarse crumbs with some pea-sized bits. (Use a pastry cutter, two knives, or pulse in processor.)
Add 3–4 tbsp ice water, 1 tbsp at a time, until dough just comes together when pressed (don’t overwork).
Shape into a disk, wrap in plastic wrap, and chill at least 30 minutes (an hour is ideal). Short on time? 20 min in the freezer will firm it up.
Cream 2 tbsp softened butter with ¼ cup maple sugar until smooth.
Add 1 egg yolk, ½ tsp vanilla, and a pinch of salt; mix.
Fold in the ½ cup ground hazelnuts until evenly combined. Frangipane should be spreadable but not runny. Chill briefly if it’s too soft.
Peel (optional), core, and thinly slice pears (aim for 1/8–1/4" slices).
Toss with 2 tbsp maple sugar, 1 tsp orange juice, ½ tsp cinnamon, and optionally 1 tbsp cornstarch (or 1 tsp if you prefer less thickening) to catch excess juices. Let it sit 5–10 minutes to macerate, then blot off any obvious puddles of juice with a paper towel. You want flavor without sogginess.
Preheat oven to 375°F (190°C). Line a baking sheet with a piece of parchment paper.
On a lightly floured surface, roll the chilled galette dough into roughly a 12" circle (about 1/8" thick). Transfer it to parchment paper and onto the cookie sheet.
Leave a 2-inch border around the edge. Spread a thin, even layer of frangipane in the center, leaving that border.
Arrange pear slices over the frangipane in a fan or spiral (overlap slightly). Tuck any smaller pieces toward the center for a neat look. If you like crunch, scatter a tablespoon or two of chopped hazelnuts over the pears (optional).
Fold the dough border over the pears in pleats, pressing gently to seal. Beat the egg in a small bowl and brush the exposed crust with it.
Mix 2 tbsp raw sugar + ½ tsp ground cardamom and sprinkle over the crust (not the pears). The sugar gives sparkle; cardamom gives that warm, floral pop.
(Optional) lightly brush pear tops with a touch of melted butter.
Bake on the middle rack for 40–45 minutes, until crust is golden, cardamom sugar is caramelized, and frangipane is set (no large jiggle). If the crust edge browns too fast, tent with foil.
If you like a slightly deeper caramelized top, you can broil for 30–60 seconds at the very end — watch like a hawk.
Remove from oven and immediately brush pears lightly with honey or maple syrup for gloss. Scatter a few thyme sprigs or extra chopped toasted hazelnuts if you used them.
Let the galette cool on a rack for at least 20–30 minutes so the frangipane sets — it will slice more cleanly and photograph better.
Serve slightly warm with a dollop of whipped mascarpone or vanilla gelato. A tiny grating of lemon zest over the mascarpone lifts the whole thing.
Notes
Keep that butter cold - for that flaky crust. Cube it, chill it, and don’t overwork the dough. Toast those hazelnuts - a quick toast in the oven brings out a deeper, richer flavor. Slice pears carefully - thin, even slices (about 1/8–1/4 inch) bake more evenly