French Mushroom and Gruyère Tart with Thyme
A savory tart featuring sautéed mushrooms and nutty Gruyère cheese nestled in a flaky pastry crust, enhanced by fresh thyme and cream. This french-inspired vegetarian (vegetarian) ready in about 40 minutes layers sliced button mushrooms, unsalted butter, olive oil 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 380 calories and feeds 4, 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 sheet (about 9x9 inches), thawed frozen puff pastry
- 10 oz, sliced button mushrooms
- 2 tbsp unsalted butter
- 1 tbsp olive oil
- 2, minced garlic cloves
- 1 tbsp fresh thyme leaves
- 1/4 cup heavy cream
- 1 cup shredded Gruyère cheese
- 1/2 tsp salt
- 1/4 tsp black pepper
- 1, beaten with 1 tsp water for egg wash egg yolk
Instructions
- Step 1: Preheat oven to 400°F. Roll out 1 sheet thawed frozen puff pastry on a parchment-lined baking sheet to smooth edges. Score a 1-inch border by lightly pressing with a knife without cutting through.
- Step 2: Heat 2 tbsp unsalted butter and 1 tbsp olive oil in a large skillet over medium-high heat. Add 10 oz sliced button mushrooms and sauté for 7-8 minutes until golden and moisture evaporates.
- Step 3: Add 2 minced garlic cloves and 1 tbsp fresh thyme leaves to mushrooms, cooking for 1 more minute until fragrant. Season with 1/2 tsp salt and 1/4 tsp black pepper.
- Step 4: Remove skillet from heat and stir in 1/4 cup heavy cream to the mushroom mixture. Spread evenly inside the scored border of the puff pastry.
- Step 5: Sprinkle 1 cup shredded Gruyère cheese evenly over the mushrooms. Brush the pastry border with beaten egg yolk mixed with 1 tsp water.
- Step 6: Bake tart for 20-22 minutes until pastry is puffed and golden, and cheese is melted and slightly browned. Let cool 5 minutes before slicing to serve.
Equipment for this recipe
Top-rated tools to make this recipe successfully.
Frequently asked questions
How long does French Mushroom and Gruyère Tart with Thyme take to make?
Total time is about 40 minutes (15 min prep + 25 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 French Mushroom and Gruyère Tart with Thyme?
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 French Mushroom and Gruyère Tart with Thyme?
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 French Mushroom and Gruyère Tart with Thyme for a different number of people?
The recipe is written for 4 servings. Multiply each ingredient by (your serving target / 4). 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.
Is French Mushroom and Gruyère Tart with Thyme vegetarian?
Yes — this recipe is tagged vegetarian based on its ingredient list. Always cross-check labels for packaged ingredients (sauces, broths, condiments) since formulations vary by brand.
