Savory Mushroom Onion Galette

The first time I made this savory mushroom and onion galette was on a rainy afternoon, craving something warm and comforting. As the buttery crust baked and the caramelized onions filled the kitchen with their sweet aroma, I knew this would become a new favorite.

I’ll never forget the first time unexpected guests arrived, and I pulled this galette from the oven just in time. Their surprised smiles and the effortless elegance made cooking feel like magic.

Ingredients

• All-purpose flour: I always reach for good quality flour to get the delicate, flaky crust just right.
• Unsalted butter: Cold and cubed, it’s the secret to that perfect tender texture.
• Yellow onion: Thinly sliced for even caramelization and sweetness.
• Cremini mushrooms: Their earthiness balances the sweet onions perfectly; fresh and cleaned well.
• Fresh thyme: Adds a fragrant herb note that ties all flavors together.
• Gruyère cheese: Grated finely to melt just right without overpowering.
• Egg: Beaten to brush the crust for a gorgeous golden finish.

Instructions

Make the Crust:

Start by whisking the flour and salt in a large bowl. You’ll feel the cold butter crumble under your fingers as you cut it in, which means that flaky texture is coming. Add ice water slowly until the dough just comes together; it should feel cool and slightly sticky. Form a disk, wrap it up, and chill to relax the gluten and firm up the butter.

Prepare the Filling:

Heat olive oil and butter in a skillet and listen to the gentle sizzle as you add the sliced onions. Stir occasionally until they turn golden and sweetly caramelized, about 15 minutes. Add garlic, sauté for a minute before stirring in mushrooms, thyme, salt, and pepper. Cook until mushrooms release their liquid and brown beautifully. Stir in fresh parsley and let the filling cool a bit to meld the flavors.

Assemble the Galette:

Roll out the dough on a floured surface to a 12-inch circle. Transfer it gently to a baking sheet lined with parchment. Sprinkle half the grated cheese in the center, leaving a border, then spread the mushroom filling over it. Add the remaining cheese on top and carefully fold the edges of the dough over the filling, creating lovely pleats. Brush with beaten egg for that golden shining crust.

Bake and Finish:

Place your galette in a preheated 400°F oven and bake for 30–35 minutes until the crust is crisp and golden. Let it cool slightly before slicing, then sprinkle with flaky sea salt and extra parsley if you like for that final savory pop.

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This galette isn’t just a dish; it became a celebration on a chilly night when family gathered around the table, savoring each buttery bite and sharing stories.

Keeping It Fresh

Store leftovers wrapped tightly in plastic wrap in the fridge. To bring back that fresh-from-the-oven crunch, reheat briefly in a warm oven instead of the microwave.

When You're Missing Something

If you don’t have Gruyère, Parmesan makes a lovely substitute. And if fresh thyme isn’t available, dried thyme works well but use half the amount to avoid overpowering.

Serving Ideas That Clicked

This galette pairs beautifully with a crisp green salad or a light soup for a cozy yet sophisticated meal.

• Don’t forget to sprinkle a pinch of flaky sea salt just before serving — it elevates flavors in a subtle way.
• Adding a splash of white wine to the mushroom sauté turns it into a delightful treat.
• Leftover galette makes a tempting breakfast or brunch item when reheated gently.

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Thanks for spending this time in the kitchen with me — I hope this galette brings warmth and smiles whenever you make it.

Questions & Answers

→ What type of mushrooms work best?

Cremini or button mushrooms are ideal for their texture and mild flavor, complementing the caramelized onions well.

→ How to achieve a flaky crust?

Use cold, cubed butter cut into the flour and avoid overworking the dough. Chilling the dough before baking helps maintain flakiness.

→ Can this be made vegan?

Yes, substitute vegan butter for the crust and use plant-based cheese or omit cheese altogether for a vegan-friendly version.

→ How to get the onions caramelized properly?

Cook sliced onions slowly over medium heat with occasional stirring until they turn golden and sweet, about 15 minutes.

→ Is it necessary to use herbs?

Fresh thyme and parsley enhance the savory profile, but you can adjust or omit according to taste preferences.

→ What wine pairs well with the galette?

A crisp white wine like Sauvignon Blanc complements the buttery crust and earthy mushrooms perfectly.