Onion & Cheese Quiche

This quiche is fully from scratch, crust and all. The pastry uses club soda instead of ice water, which creates a lighter, flakier shell, and the letter-fold technique borrows from puff pastry to build visible layers that shatter when you cut into them.

Three large onions sliced paper-thin and cooked slowly in butter until translucent form the base layer inside the crust. They’re not caramelized here, just softened, which gives the quiche a sweet, mild onion flavor that doesn’t compete with the cheese.

Half a pound of grated Swiss cheese (or Gouda, if you want something a bit creamier) gets tossed with a tablespoon of flour before going in. That flour coating prevents the cheese from clumping in the custard and helps it distribute evenly through every slice.

The custard itself is three eggs beaten with a full cup of heavy cream, seasoned with salt, pepper, and nutmeg. That nutmeg is classic in French egg custards for a reason. It adds a warm, almost invisible spice note that rounds out the richness without announcing itself.

Two-temperature baking is the final detail. Starting at a higher heat sets the custard quickly, then dropping the temperature lets the center cook through gently without browning the top too much or puffing up and then collapsing.

Pro Tips

• Keep everything cold when making the crust. Cold butter creates steam pockets that make flaky layers
• Chill the dough twice: once before rolling, once after the letter fold. Skipping either rest makes the dough tough
• Cool the cooked onions completely before assembling. Hot onions will melt the butter in the crust
• The quiche is done when the center still jiggles slightly. It sets as it cools

Variations

• Gruyere version: Swap Swiss for Gruyere for a nuttier, more complex cheese flavor
• Bacon and onion: Add ¼ pound of crispy crumbled bacon to the onion layer for a Quiche Lorraine-style variation
• Caramelized onion: Cook the onions longer until deeply golden for a sweeter, more intense onion flavor