Ingredients
Scale
For the filling:
- 8 ounces mixed mushrooms (oyster, shiitake, and baby bella), sliced
- 2 leeks, white and light green parts only, cleaned and thinly sliced
- 7 asparagus spears, woody ends trimmed, cut into 1-inch pieces (reserve a few tips for the top)
- 3 teaspoons unsalted butter
For the custard:
- 4 large eggs
- ½ cup whole milk
- ½ cup half and half
- 1 teaspoon Diamond Crystal kosher salt (if using Morton’s, use ½ teaspoon)
- ½ teaspoon freshly ground black pepper
- ½ teaspoon freshly grated nutmeg (use a microplane for the best flavor)
For assembly:
- 1 8-inch pastry shell, pre-baked (blind baked) until just set
- 1½ cups Gruyère cheese, freshly shredded
Instructions
- Preheat your oven to 375°F (190°C). Place a baking sheet on the middle rack to preheat as well, this helps the bottom crust crisp up.
- Melt the butter in a large skillet over medium heat. Add the sliced leeks and cook, stirring occasionally, for about 5 minutes until softened and just starting to turn golden at the edges.
- Add the mushrooms to the skillet and increase the heat slightly to medium-high. Cook for 6 to 8 minutes, stirring occasionally, until the mushrooms have released their liquid and are golden brown. Season lightly with salt and pepper.
- Add the asparagus pieces (not the reserved tips) to the skillet and toss everything together for 1 to 2 minutes just to take the raw edge off. Remove from heat and let cool for 5 minutes.
- Whisk the custard in a medium bowl: combine the eggs, whole milk, half and half, kosher salt, black pepper, and freshly grated nutmeg. Whisk until fully combined and slightly frothy.
- Assemble the quiche by scattering half the shredded Gruyère over the bottom of the pre-baked pastry shell. Spread the mushroom, leek, and asparagus mixture evenly on top, then add the remaining Gruyère.
- Pour the custard slowly and evenly over the filling, allowing it to settle into the gaps. Arrange the reserved asparagus tips on top in a fan pattern.
- Bake the quiche on the preheated baking sheet for 35 to 40 minutes, until the custard is set in the center (a slight jiggle is fine, but it shouldn’t look liquid) and the top is lightly golden.
- Rest before slicing for at least 15 minutes. This is non-negotiable if you want clean, beautiful slices. Serve warm or at room temperature.
Notes
- Blind baking the shell: Pre-bake your pastry shell at 375°F for about 15 minutes with pie weights or dried beans before adding the filling. This prevents a soggy bottom.
- Make-ahead: The filling (mushrooms, leeks, asparagus) can be cooked the day before and stored in the fridge. The custard can also be whisked ahead and refrigerated overnight. Just assemble and bake when ready.
- Storage: Leftover quiche keeps well covered in the fridge for up to 3 days. Reheat individual slices in a 325°F oven for 10 to 12 minutes.
- Freezing: You can freeze baked quiche slices wrapped tightly for up to 2 months. Thaw overnight in the fridge before reheating.
- Cheese tip: Shred your own Gruyère. Pre-shredded cheese contains anti-caking agents that affect how it melts into the custard.
- Scaling up: This recipe fills one 8-inch shell comfortably. To make two, simply double everything, the filling, custard, and cheese.
- Prep Time: 20 minutes
- Cook Time: 45 minutes
- Category: Breakfast
- Method: Baking
- Cuisine: French-inspired
Nutrition
- Serving Size: 1 slice
- Calories: 380 kcal
- Sugar: 4 g
- Sodium: 420 mg
- Fat: 26 g
- Saturated Fat: 13 g
- Unsaturated Fat: 11 g
- Trans Fat: 0.3 g
- Carbohydrates: 22 g
- Fiber: 2 g
- Protein: 14 g
- Cholesterol: 165 mg