Mushroom Leek and Gruyere Mini Quiche Recipe

Why You’ll Love this Recipe

• Great leftover!
• The flavor and texture of this quiche is perfect!
• The dough is easy to make ahead of time and refrigerate or freeze until ready to use.
• The egg custard comes together in no time and is so silky!

The Secret to a Custardy French Quiche

The custard for a quiche is basically just an egg mixture with milk and cream, but the secret to making this a melt-in-your-mouth dish is how it is cooked and patience.

Quiche cooks at low temperatures for a decent amount of time, depending on how large the quiche is. If the heat is raised, the top of the quiche could form an unappealing textural film. Or even worse, the top could brown, changing the egg flavor and making an unpleasant tasting (and looking) quiche. But this recipe will take care of that worry!  

Ingredients

Here is what you need to make this mini mushroom quiche recipe:

Quiche Dough:

• All Purpose Flour: All-purpose flour is the best flour to use for the dough.
• Unsalted Butter: Cold, unsalted butter is used to build the base of the dough and makes the dough flaky and delicious when cooked.
• Salt: Kosher salt flavors the dough.
• Egg Yolk: An egg yolk brings the dough together and gives it richness.
• Water: Just a bit to bring the dough together.

Egg Custard:

• Whole Milk: Whole milk is a must here due to the fat content.
• Heavy Cream: The cream gives the body and butterfat to the custard.
• Egg Yolks: The egg yolks bring richness to the custard.
• Whole Large Eggs: The whites in the egg helps lighten the custard as it cooks.
• Black Pepper: Just a pinch in the custard helps with flavor.

Fillings:

• Mushrooms: Use your favorite, but we love hen of the woods (maitake), shiitake, chestnut and other varieties known for their flavor. Or use a combination or a wild mushroom mixture.
• Unsalted Butter: Unsalted butter to cook both the mushrooms and the leeks.
• Kosher Salt & Black Pepper: A pinch of each is used with the mushrooms and leeks.
• Dried Thyme: Just a pinch of dried thyme really complements the mushrooms in this dish.
• Dry White Wine: White wine, such as Pinot Grigio, really enhances the flavor of the mushrooms.
• Leeks: We use just the white part of the leeks for this recipe. Sautéed leeks have a great, underrated flavor that works perfectly in this quiche.
• Gruyere Cheese: Just a little of this flavorful alpine cheese enhances the flavor of the quiche so much!
• Fresh Thyme: For garnish.

See recipe card below for quantities.

Substitutions

Here are a couple of common substitutions for the ingredients in this recipe:

• Dough/Crust: Store-bought pie dough or premade frozen store-bought pie crust can be used, although the dough in this recipe is fantastic. But for convenience, you could buy the crust or even use puff pastry if you want a slightly different texture.
• Leeks: Leeks have a fantastic mild sweet onion flavor, which is great in this recipe. But you can use shallots or sweet yellow onions if you prefer. 
• Gruyere Cheese: Any alpine cheese, such as Emmental, American Swiss cheese, and others can be substituted with great results.
• Filling: You can use the egg custard base with a variety of fillings if you don't like this mushroom and leek combo.

How to Make Mushroom Mini Quiche

The dough is certainly the long pole in the tent here. It does take some time to prepare, but it is definitely worth the effort! Once the dough is done, the custard takes no time to make and the additional ingredients just take about 10-15 minutes to prepare. Once the custard and add-ins are assembled in the pie crust, the quiche bakes at a low temperature until it sets. The velvety texture of a well made quiche is absolutely amazing!

Equipment

Here is what you need to make this dish

• Food processor: This tool comes in very handy when making the crust as it cuts the cold butter into the flour for you instead of using a bench scraper and doing it by hand
• Rolling pin: To roll out the dough
• Medium bowl and whisk: To make the custard
• Mini Tart Pans: (4-inch diameter with removable bottoms) or ring molds to make your quiche: This is based on mini quiche that are made in a 4” tart pan.
• Sauté pan: To cook the mushrooms and leeks.
• Pie Weights or Dried Beans: These are used while blind baking the crust so that it doesn't puff up. 
• Baking sheet: A baking sheet tray to place your mini quiches on will make transferring them to and from the oven much easier and catch any overflow.

Step-by-Step Instructions

Make the Dough to Rest

• Add the flour, cold butter and salt to the food processor and pulse until the butter is smaller than pea-sized (more like rice). Remove the flour mixture to a work surface and create a well in the middle. Add the egg yolk and water to the center of the well. Stir with a fork and gradually incorporate the flour and butter mixture into the wet ingredients.
• Once incorporated enough to use your hands, knead the dough for about a minute until fully incorporated. Divide into six equal portions and shape into discs - about ¾” thick. Wrap in plastic wrap and put in the refrigerator for 20 minutes or up to 24 hours.

Make the Additions

• While the dough rests in the refrigerator, heat a sauté pan over medium heat. Add the butter until melted. Add the mushrooms, a pinch of salt and pepper, and the dried thyme. Sauté the mushrooms for about 3 minutes until they absorb and then release some of the liquid. Add the wine and cook for a couple minutes until the wine is about gone. Remove the mushrooms to a bowl and set aside.
• In the same pan, add the remaining butter and when it melts, add the leeks and a pinch of salt and pepper. Cook for about 4-5 minutes over medium heat or until the leeks are soft. Remove to a bowl and set aside. 

Form the Dough and Blind Bake

• Preheat the oven to 350°F. Once the dough has rested, remove it from the refrigerator. On a lightly floured work surface, roll the dough to ⅛” thickness. Spray the tart pans or whatever you are using with nonstick spray and mold the dough into each pan. With a fork, dock the dough by making holes on the bottom and sides of the dough so air can escape and the dough doesn’t puff up.
• Line the inside of the dough with plastic wrap (or parchment paper) and fill with pie weights or dried beans. Fold the plastic into the center of the dough over the weights so the plastic isn’t touching the sides of the metal pan. Place the tart pans on a large sheet tray then place the sheet tray in the oven and blind bake the crusts for 25 minutes. 
• Remove the crusts from the oven and remove the plastic wrapped weights. Place the empty crusts back into the oven for 25-30 minutes or until the crust is golden brown. Remove from the oven and brush a small amount of custard over the holes in the crust. Return to the oven for 3 minutes. Remove the crusts again and let them cool before filling.
• Turn the oven down to 275°F. 

Make the Custard

• After the crusts have blind baked but before they go into the oven for the second time, make the custard. Combine all the ingredients in a mixing bowl and whisk thoroughly. Set aside in the fridge until ready to use. 

Assemble the Quiche and Bake

• Assemble the quiches by adding some custard, then some mushrooms, leeks, and a little cheese. Then fill each quiche crust with the custard, gently pouring it into the crusts being careful not to let it overflow into the tart pans. Place the sheet tray of quiches in the 275°F oven for 20 minutes and check for doneness by wiggling the quiche gently. If it ripples and is very giggly in the middle, return to the oven for 5 minutes. Repeat this process until the quiche is just set.
• One done, remove from the oven and let cool so you can handle the quiche. Gently remove it from the pan and serve with some fresh thyme on top! 

Variations

Here are a couple ways to change up this recipe:

• You can always add some sort of meat, such as ham, bacon, pancetta, or prosciutto. These fillings should be cooked first before adding them to the quiche.
• You can make an herbed crust by adding some dried or fresh herbs (thyme, basil, etc.) to the dough.
• Change up the filling! The egg custard base can be used with a variety of fillings. Some of our favorites are fresh spinach with goat cheese and prosciutto, diced tomatoes with basil and parmesan cheese, or ham and cheddar cheese. Use your favorite vegetables, such as onions and bell peppers, or any other ingredient in your quiches. And if you haven't had a quiche with feta cheese in it...you're missing out!

Storage

How to store leftover mushroom mini quiche:

• The cooked quiches should be cooled to room temperature then they can be wrapped in plastic or placed in an airtight container and kept in the refrigerator for up to 5 days.

How to reheat leftover quiche:

• Reheat quiches in a 325°F oven until warmed through.

Can you freeze leftover quiche?

• Quiche freezes very nicely and can be reheated from frozen at a low temperature (325°F). They will be perfect for a month in the freezer, then start to degrade in texture afterwards. Use within 3 months.

Troubleshooting

If your quiche doesn’t seem to be set (it is very jiggly in the middle while baking) just be patient. Do not turn the oven temperature up. It will set, but if you turn the heat up you could ruin the custard texture and get an unpleasant cooked brown egg film on top.

What to serve with Mushroom Mini Quiche

A quiche is perfectly served with some fresh fruit and maybe some slightly sweetened crème fraîche or whipped cream. A small salad with a vinaigrette also works very well with a quiche.

What Wines To Drink with Quiche

Our favorite wine to enjoy with quiche is a dry sparkling wine or Champagne. Any dry white wine will work well, especially Pinot Grigio or a dry riesling. Beaujolais is also a great choice here if you want a light bodied red wine. Just avoid any wine aged in oak barrels (like an oaky Chardonnay) as it will clash with the quiche. But if serving at a brunch, a mimosa (or two) would be welcomed as well!