Mushroom & Onion Quiche

Stewing the mushrooms and onions in butter before they go into the pie shell is what separates a great quiche from a watery one. That slow cook drives off moisture and concentrates the flavors, so your custard stays creamy instead of soggy.

Half a pound of Swiss cheese goes right on top of the vegetables, forming a melty layer that holds everything in place. The custard itself is rich: eggs beaten with heavy cream and milk, seasoned simply with salt, pepper, and a sprinkle of nutmeg on top. That nutmeg is subtle but essential. It brings warmth that ties the earthy mushrooms and sweet onions together.

The quiche bakes until the center is just set. A slight jiggle is fine; it firms up as it cools. Overbaking dries out the custard and turns it rubbery.

Pro Tips

• Slice mushrooms thick, about ¼ inch. Thin slices dissolve into the custard and you lose that satisfying bite.
• Let the stewed vegetables cool for a few minutes before adding the custard. Hot filling can start cooking the eggs from the bottom up, creating an uneven set.
• Use an unbaked pie shell. Pre-baking isn’t necessary here since the long bake time crisps the crust through.

Variations

• Add 4 strips of crumbled cooked bacon for a classic quiche Lorraine twist.
• Swap Swiss for Gruyere for a nuttier, more complex cheese flavor.
• Toss in a handful of fresh thyme leaves with the mushrooms while stewing.