Rustic Gex-Style Mushroom and Gruyère Tart
A flaky pastry tart filled with sautéed wild mushrooms and nutty Gruyère cheese, inspired by the rich flavors of the Ain region. This French-inspired vegetarian recipe, ready in about 80 minutes, layers all-purpose flour, unsalted butter, cold water into a dessert worth slowing down for — great for weekend baking, holiday tables, or any time you want a sweet payoff at the end of a meal. Each serving lands at about 320 calories and feeds 6, so it slots into a weekend bake or a special-occasion dessert tray. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.
Ingredients
- 1 1/4 cups all-purpose flour
- 7 tbsp, cold and cubed unsalted butter
- 3 tbsp cold water
- 1/4 tsp salt
- 10 oz, sliced mixed wild mushrooms
- 2 tbsp olive oil
- 2, minced garlic cloves
- 1 tsp, chopped fresh thyme
- 1 cup, grated Gruyère cheese
- 1, beaten egg
- 1/4 cup heavy cream
- to taste black pepper
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Equipment for this recipe
Top-rated tools to make this recipe successfully.
Instructions
- Step 1: In a large bowl, combine 1 1/4 cups all-purpose flour and 1/4 tsp salt, then cut in 7 tbsp cold cubed unsalted butter using a pastry cutter until mixture resembles coarse crumbs. Add 3 tbsp cold water gradually until dough just comes together. Form into a disk, wrap in plastic, and chill for 30 minutes.
- Step 2: Preheat oven to 375°F. Heat 2 tbsp olive oil in a skillet over medium heat, add 2 minced garlic cloves and sauté for 30 seconds until fragrant. Add 10 oz sliced mixed wild mushrooms and 1 tsp chopped fresh thyme, cooking for 6-8 minutes until mushrooms release moisture and brown. Season with black pepper and remove from heat.
- Step 3: Roll chilled pastry dough on a floured surface into a 12-inch circle and transfer to a 9-inch tart pan, pressing dough into edges. Prick the bottom with a fork.
- Step 4: Spread the mushroom mixture evenly over the pastry base. In a small bowl, whisk 1 beaten egg with 1/4 cup heavy cream and 1 cup grated Gruyère cheese, then pour over mushrooms.
- Step 5: Bake tart for 30-35 minutes until crust is golden and filling is set with a bubbly, lightly browned top. Allow to cool for 10 minutes before slicing and serving warm.
Frequently asked questions
How long does Rustic Gex-Style Mushroom and Gruyère Tart take to make?
Total time is about 80 minutes (40 min prep + 40 min cook). Most home bakers find this fits a weekend afternoon; chill or store as the recipe directs before serving.
How do I store leftover Rustic Gex-Style Mushroom and Gruyère Tart?
Cool fully before storing. Most baked desserts keep at room temperature in an airtight container for 2–3 days, or in the fridge for up to 5 days. Cream- or custard-based desserts must go in the fridge within 2 hours; reheat gently or serve cold per the recipe.
Can I substitute ingredients in Rustic Gex-Style Mushroom and Gruyère Tart?
Yes — most ingredients in this recipe have flexible swaps. For oil, use any neutral high-smoke-point oil (avocado, grapeseed, refined coconut). For aromatics, dried herbs at ⅓ the volume of fresh work in a pinch. The full ingredient list is shoppable on Instacart so you can see substitutes in real time.
How do I scale Rustic Gex-Style Mushroom and Gruyère Tart for a different number of people?
The recipe is written for 6 servings. Multiply each ingredient by (your serving target / 6). Cook time stays roughly the same up to 2x; for 3-4x batches, switch from a skillet to a sheet pan or stockpot so the food isn't crowded — overcrowding steams instead of browns.
What goes well with Rustic Gex-Style Mushroom and Gruyère Tart?
French vegetarian like this pair well with a simple grain (rice, couscous, or crusty bread), a quick salad with acid (lemon vinaigrette, pickled onions), and a pan sauce or yogurt-based dip. Tap "Plan a meal with the AI" to get specific side suggestions.
