I wish I had better photographic evidence of how gorgeous and tasty this galette was—but when something this good comes out of your oven, taking a photo suddenly drops on the priority list. Eating a slice while it's warm and gooey? Yeah, that takes precedence.
This is butternut squash like you've never had it before. It's tender but not mushy, comforting but not too rich, and pairs perfectly with caramelized onions, freshly grated fontina cheese, and a sprinkling of fresh thyme. The crust is the other star, here, arriving from the oven with a croissant-like finish thanks to a quick brush of egg-wash.
I'm a big fan of galettes because of their free-form shape. You don't need the right size pie plate or a spring-form cake pan. You just need a plain ol' baking sheet! I will give you a fair warning, though: this thing is HUGE. Unless you're feeding a family, I'd suggest making two smaller galettes and freezing one for later enjoyment. It re-heats wonderfully.
Butternut Squash and Caramelized Onion Galette
Serves 8. Makes 1 large 12-inch galette, or you can split the filling and dough in half and make two smaller ones.
For the crust
- 2 cups all-purpose flour
- 1/2 cup whole-wheat flour
- 1/2 tsp. table salt
- 16 tbsp. (2 sticks) unsalted butter
- 1/2 cup full-fat plain Greek yogurt (or sub sour cream)
- 1 tbsp. white wine vinegar
- 1/3 cup cold water
For the filling
- 1 large butternut squash
- 3 tbsp. extra-virgin olive oil
- 1½ tsp. table salt
- Freshly ground black pepper
- 1 tbsp. unsalted butter
- 1 - 1 1/2 large sweet onions (such as Vidalia), halved, thinly sliced in half-moons
- 1/4 tsp. sugar
- 1/4 tsp. cayenne pepper
- 1 1/2 cups grated Italian Fontina cheese
- 1 tsp. chopped fresh thyme
- 1 egg beaten with 1 tsp water, for glaze
For the crust:
Combine the flours and salt in a large bowl. Add the sticks of butter and, using a pastry blender or your fingertips, break up the butter until the texture is like cornmeal. In a smaller bowl, whisk together the yogurt, vinegar and water. Pour over the butter-flour mixture and stir with a spoon until a dough forms, kneading it once or twice on the counter if needed. Pat the dough into a ball, wrap it in plastic wrap, and chill in the fridge for at least an hour or up to two days.
To prepare squash:
Preheat the oven to 400 degrees F. Peel the squash, cut in half length-wise, and scoop out the seeds. Cut into small chunks. Pour 2 tbsp. olive oil onto a large baking sheet and spread it around until slick. Place the squash chunks onto the baking sheet in one layer, sprinkle with ½ tsp. of the salt and freshly ground black pepper, and roast for 30 minutes, or until squash is tender, turning the pieces occasionally. Set aside to cool slightly. Leave the oven on.
While the squash is roasting, melt the butter and remaining tablespoon of olive oil in a large skillet. Add the onions, sugar, and remaining tsp. salt. Cook, stirring occasionally, until soft, tender, and caramelized, about 25 minutes. Add the cayenne pepper.
Mix the squash, caramelized onions, cheese and thyme together in a bowl.
On a floured work surface, roll out the dough into a large round, about 16 inches wide. Depending on the amount of butternut squash you have, you may find this is a tad too much dough. Feel free to trip a little off the edges, because if the dough is rolled out too thick, the bottom crust won't bake all the way through.
Transfer to a parchment-lined baking sheet. Spread the squash-and-cheese mixture over the dough, leaving a 2 to 2½-inch border. Fold the border over the squash and cheese, pleating the edge to make it fit. The center will be open. Brush the outside of the crust with the egg-yolk wash.
Bake until golden brown, 30 to 40 minutes. Remove the galette from the oven, let stand for five minutes, then slide onto a serving plate. Cut into wedges and serve hot, warm or at room temperature.
Recipe adapted from seven spoons.