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Mushroom, Onion and Thyme Galette

For the crust: I highly recommend using a food processor for the crust but if you don't have one, simply use a pastry cutter to break up and combine the cold butter with the flour for the crust. This method will take longer.
Prep Time20 mins
Cook Time1 hr 40 mins
Total Time2 hrs
Course: Meal
Keyword: baking, brunch, galette, mushrooms, savory tart
Servings: 6
Author: Hip Foodie Mom


For the crust:

  • 1 1/4 cups all-purpose flour
  • 3/4 teaspoon sea salt
  • 1/2 cup (1 stick) very cold unsalted butter cubed and immediately added
  • 1/4 cup cold ice water
  • 1 egg slightly beaten, for egg wash

For the filling:

  • 3 tablespoons olive oil or unsalted butter split
  • 2 cups onions sliced from root to tip; long strips
  • 3 to 4 cups mushrooms sliced; I recommend Cremini
  • 2 to 3 tablespoons fresh thyme leaves only
  • kosher salt
  • 2 to 3 teaspoons balsamic vinegar
  • 1/4 cup mozzarella cheese

Special equipment needed:

  • food processor or pastry blender or you could even use 2 forks
  • rolling pin


For the crust:

  • Using your food processor, combine the flour, salt and butter and process for about 5 seconds. Sprinkle the ice water over the flour mixture and pulse until the pastry just begins to come together, about 10 seconds; you should still be able to see small pieces of butter in it.
  • Transfer the pastry dough to a lightly floured work surface, gather it together to combine everything and roll out to a 12 inch circle. Transfer the dough to a prepared, parchment lined baking sheet and refrigerate while you prepare the filling (You can also roll out the dough and use it right away if needed).

For the filling:

  • Heat 2 tablespoons of olive oil, or butter, in a large sauté pan over medium heat. After a minute or 2, add the onions and stir continuously until softened and tender, for about 15 to 18 minutes. To caramelize the onions for more flavor, continue cooking for another 20 minutes. Remove from pan and set aside.
  • Using the same pan, use the remaining tablespoon of olive oil and, after a minute or 2, add the sliced mushrooms, thyme and season with a little salt and let cook until softened and tender, for about 8 to 10 minutes.
  • Add the balsamic vinegar and reduce the heat to medium low. Cook for another 5 minutes, remove from the heat and combine with the cooked onions. Set aside.

To assemble the galette:

  • Preheat your oven to 375 degrees. Remove your dough from the refrigerator and spoon in the onion, mushroom mixture in the center of the dough, leaving a 2-inch border all around. Gently fold over the pastry border, overlapping the edges as much as possible and gently pressing the folds together.
  • Brush the folded edges of the crust with the egg wash and bake for 30 to 40 minutes, or until the crust has become a lovely golden brown. During the last 10 minutes or so of baking, sprinkle on the shredded mozzarella cheese. Use as little or as much as you want. Let cool for about 20 minutes before cutting and serving. Enjoy!