Mushroom Onion Quiche
A golden, savory quiche filled with earthy sautéed mushrooms and sweet caramelized onions in a rich custard.
Ingredients
- •1 refrigerated or homemade pie crust (9-inch)
- •2 tablespoons unsalted butter (30g)
- •1 tablespoon olive oil (15ml)
- •2 medium yellow onions, thinly sliced
- •8 ounces cremini mushrooms, sliced (225g)
- •2 cloves garlic, minced
- •3 large eggs
- •1 cup heavy cream (240ml)
- •1/2 cup whole milk (120ml)
- •1 cup shredded Gruyere or Swiss cheese (100g)
- •1/2 teaspoon kosher salt
- •1/4 teaspoon black pepper
- •1/4 teaspoon ground nutmeg
- •1 tablespoon fresh thyme leaves
Instructions
- 1
Preheat your oven to 375°F (190°C) and fit the pie crust into a 9-inch pie dish, crimping the edges.
- 2
Line the crust with parchment paper and fill with pie weights or dried beans, then bake blind for 12 minutes until set.
- 3
Remove the weights and parchment, and bake for another 5 minutes until the bottom is lightly golden, then remove from the oven and reduce oven temperature to 350°F (175°C).
- 4
Heat the butter and olive oil in a large skillet over medium heat.
- 5
Add the sliced onions and cook, stirring occasionally, for 15 minutes until soft and deeply caramelized.
- 6
Add the sliced mushrooms and minced garlic to the skillet with the onions, cooking for another 8 minutes until the mushrooms are browned and their liquid has evaporated.
- 7
Stir in the fresh thyme, season with a pinch of salt and pepper, then remove from heat and let cool slightly.
- 8
In a large bowl, whisk together the eggs, heavy cream, whole milk, salt, pepper, and ground nutmeg until smooth.
- 9
Scatter the cooked mushroom and onion mixture evenly across the bottom of the blind-baked pie crust.
- 10
Sprinkle the shredded Gruyere cheese directly over the vegetables.
- 11
Carefully pour the egg and cream custard mixture over the cheese and vegetables in the crust.
- 12
Bake at 350°F (175°C) for 30 to 35 minutes, or until the center is set and the top is puffed and golden brown.
- 13
Allow the quiche to cool for at least 15 minutes before slicing to ensure clean portions.
💡 Chef tips
- For a smoky flavor without meat, you can add a pinch of smoked paprika to the onion mixture.
- Make-ahead tip: You can caramelize the onions and mushrooms a day in advance and store them in the refrigerator.
- To store, cover tightly and keep in the refrigerator for up to 3 days; reheat gently in a 350°F oven before serving.
✅ How it should turn out
The finished quiche features a buttery, flaky crust holding a set, custard-like filling that smells deeply savory with caramelized onions, earthy mushrooms, and melted cheese, cutting into neat, beautiful wedges.