Mushroom Quiche Lorraine Recipe

This mushroom quiche is a quiche lorraine with mushrooms: a buttery homemade crust filled with crisp bacon, browned mushrooms, onion and Gruyère, set in a custard of 4 eggs, 1 cup heavy cream and 1/2 cup milk. It takes about 1 hour 40 minutes, including 30 minutes chilling the dough, and makes 6 slices.

Two things keep it from going watery. Cook the mushrooms until their liquid is gone and they start to brown. Then take the quiche out while the center still wobbles a little, because it keeps setting as it rests.

The Crust, the Filling and the Timeline

• Crust: 1 1/4 cups all-purpose flour, 1/2 teaspoon salt, 1/2 cup cold unsalted butter, 3 to 4 tablespoons ice water
• Filling: 6 slices bacon, 1 cup sliced mushrooms, 1 small onion, 1 cup shredded Gruyère or Swiss cheese
• Custard: 4 large eggs, 1 cup heavy cream, 1/2 cup whole milk, 1/4 teaspoon nutmeg, salt and black pepper
• Oven: 375°F (190°C) to blind bake the crust, then 350°F (175°C) for the quiche
• Time: 25 minutes prep, about 1 hour 40 minutes in total including chilling
• Makes: 6 slices

Mixing and Blind Baking the Butter Crust

Rub the cold butter into the flour and salt with your fingertips until it looks like coarse crumbs with a few pea size bits left. Add the ice water a tablespoon at a time, only until the dough holds together when you squeeze a handful. Flatten it into a disk, wrap it, and chill it for at least 30 minutes. Those cold bits of butter turn to steam in the oven, and the steam is what makes the crust flaky.

Roll it out and ease it into a tart or pie pan without stretching it, then trim the edge and prick the base with a fork. The photos show a fluted tart pan; a standard 9 inch pie dish works too. Line it with parchment, fill it with baking weights or dried beans, and bake at 375°F (190°C) for 15 minutes. Lift out the weights and bake another 5 to 7 minutes, until the base looks dry and lightly golden. If you already have a favorite pie crust recipe, it works here too.

Please do not skip the blind bake. A raw base under liquid custard comes out pale and soggy. See a small crack after baking? Press a scrap of leftover dough over it, or the custard will run underneath.

Browning the Mushrooms So the Filling Stays Dry

Cook the chopped bacon over medium heat until crisp, then lift it onto a paper towel. In the same pan, cook the onion and mushrooms until soft and lightly browned.

Mushrooms are mostly water. First they shrink and flood the pan with liquid. Keep going until that liquid has boiled away and the edges turn brown, which takes longer than it looks like it should. Any water left in them seeps into the custard in the oven and leaves a wet layer just above the crust. The browning also gives the deep, savory flavor that makes this more than an egg bake.

Cremini mushrooms taste deeper; button mushrooms are milder and work fine.

The Custard Ratio: 4 Eggs to 1 1/2 Cups Dairy

Whisk the 4 eggs with 1 cup heavy cream, 1/2 cup whole milk, the nutmeg, salt and pepper. Go easy on the salt. Bacon and Gruyère both bring plenty. Whisk until smooth with no streaks of white, but stop before it turns frothy, since foam bakes into a spongy top.

Cream gives the custard its silky set, and the milk keeps it from feeling heavy. Swapping all the cream for milk makes a looser custard that sets softer and weeps more easily. The same custard is a good base for other quiche fillings: keep the eggs and dairy as they are and use about 2 cups of cooked, well drained filling plus the cup of cheese.

Filling the Crust and Reading the Wobble

Set the baked crust on a baking sheet, which makes a full quiche far easier to carry. Spread the bacon, mushrooms and onion over the base and scatter the cheese on top. Pour the custard in slowly so it settles around the filling instead of pushing it to one side.

Bake at 350°F (175°C) for 30 to 35 minutes. It is done when the edges are puffed and set and the center still has a slight wobble, like set gelatin, when you nudge the pan. A knife slid in halfway between the edge and the center should come out clean. Wait until the middle is firm and the eggs overcook, so the custard turns rubbery and weeps.

Let it cool for 10 to 15 minutes before slicing. The center finishes setting as it rests, and the slices come out clean.

Mushroom Quiche vs Quiche Lorraine

A traditional quiche lorraine is bacon, eggs and cream baked in a pastry crust, and many versions add Gruyère. A plain mushroom quiche is usually vegetarian, built on mushrooms, onion and cheese. This recipe sits between the two. It keeps the bacon and Gruyère of a quiche lorraine and adds mushrooms and onion, so each slice tastes smoky and earthy at once.

Swaps That Still Work

• No bacon: cook the onion and mushrooms in 1 tablespoon of butter instead. You can use 2 cups of mushrooms to fill the space the bacon leaves, and add a little more salt to the custard.
• Store-bought crust: a refrigerated pie crust is fine. Blind bake it the same way so the base stays crisp.
• Cheese: Gruyère is nutty and melts smoothly; Swiss is milder. Both are on the recipe card.

Making It Ahead and Reheating Slices

Cool the quiche completely, cover it, and keep it in the fridge for up to 3 days. Reheat it whole or in slices at 325°F, loosely covered with foil, for 15 to 20 minutes until warm in the middle. A microwave works for a single slice, though the crust softens. To freeze, wrap the cooled quiche well and freeze it for up to 2 months, then thaw it overnight in the fridge before reheating.

You can also blind bake the crust a day early and keep it covered at room temperature. In the morning, all that is left is the filling and 35 minutes in the oven.

Serve it warm or at room temperature with a green salad, fruit, or roasted potatoes. For a brunch table, it sits well next to sour cream scones or coffee cake muffins. Feeding a crowd? Overnight breakfast casserole, eggs benedict casserole and tater tot breakfast casserole can all be prepped the night before too.

Quiche Lorraine With Mushrooms: Short Answers

Why is my mushroom quiche watery?

Usually the mushrooms went in before their liquid cooked off, or the quiche baked until firm and the custard wept. Brown the mushrooms until the pan is dry, and take the quiche out while the center still wobbles.

Do you cook mushrooms before putting them in quiche?

Yes. Raw mushrooms release their water into the custard as it bakes. Cook them first until they stop giving off liquid and start to brown.

Can you eat quiche cold?

Yes. It slices cleanly straight from the fridge and is just as good at room temperature, which makes it handy for picnics and packed lunches.