Savory Mushroom Onion Galette (Printable)
Rustic tart with caramelized onions, sautéed mushrooms, and herbs in a flaky, buttery crust.
# What You'll Need:
→ Crust
01 - 1 1/4 cups all-purpose flour
02 - 1/2 teaspoon salt
03 - 1/2 cup unsalted butter, cold and cubed
04 - 1/4 cup ice water
→ Filling
05 - 2 tablespoons olive oil
06 - 1 tablespoon unsalted butter
07 - 1 large yellow onion, thinly sliced
08 - 2 cloves garlic, minced
09 - 12 ounces cremini or button mushrooms, cleaned and sliced
10 - 1 teaspoon fresh thyme leaves
11 - 1/2 teaspoon salt
12 - 1/4 teaspoon freshly ground black pepper
13 - 1/4 cup grated Gruyère or Parmesan cheese
14 - 1 tablespoon chopped fresh parsley
→ Assembly
15 - 1 egg, beaten (for egg wash)
16 - Flaky sea salt, for garnish (optional)
# How To Make:
01 - Combine flour and salt in a large bowl. Cut in cold butter until mixture resembles coarse crumbs. Gradually add ice water, mixing until dough just forms. Shape into a disk, wrap tightly, and refrigerate for 30 minutes.
02 - Heat olive oil and butter in a skillet over medium heat. Add sliced onions and cook, stirring occasionally, until golden and caramelized, about 15 minutes.
03 - Stir in minced garlic and cook for 1 minute. Add mushrooms, thyme, salt, and pepper. Sauté until mushrooms release liquid and brown, about 8 to 10 minutes. Remove pan from heat and stir in chopped parsley. Let mixture cool slightly.
04 - Preheat oven to 400°F. On a floured surface, roll chilled dough into a 12-inch circle. Transfer to a parchment-lined baking sheet.
05 - Sprinkle half of the grated cheese onto the center of the dough, leaving a 2-inch border. Spread the mushroom and onion filling over the cheese. Top with remaining cheese.
06 - Fold dough edges up over filling, pleating as needed to form a rustic border. Brush crust with beaten egg to glaze.
07 - Bake for 30 to 35 minutes until the crust is golden and crisp. Allow to cool slightly before slicing.
08 - Optionally sprinkle flaky sea salt and extra parsley on top before serving.
# Expert Tips:
01 -
- It feels like sharing a cozy secret with a friend, combining flaky crust with rich, earthy mushrooms and sweet onions.
- This recipe quickly became a favorite because it’s elegant enough to impress yet simple enough for a weeknight treat.
02 -
- Chilling the dough before baking is essential; skipping this step leads to a tough crust instead of the tender, flaky one you want.
- Caramelizing the onions slowly unlocks their sweetness and makes all the difference in flavor depth.
03 -
- Use cold butter straight from the fridge for the crust to ensure it flakes up beautifully during baking.
- The secret to a perfect galette is not overfilling it — keeping that folded edge sturdy but delicate keeps everything intact.