Quiche is essentially an custard made with milk and eggs poured into a pie crust and baked. You want just enough eggs to set the milk, but not so many that the quiche becomes rubbery. You want a bit of wobble in your quiche as it comes out of the oven. Wobble means silky, melt-away custard in every bite.

The fool-proof part comes courtesy of the French. They are masters of the quiche and long-ago settled on the perfect formula of one part egg to two parts milk. A standard large egg weighs two ounces and a cup of milk is eight ounces, so a good rule of thumb is two eggs per cup of milk. I like to bump this up a bit to make a more substantial quiche and usually go with three eggs and a cup and a half of milk in a nine-inch pie crust.

Cheese makes a luscious custard even more luscious. There’s no hard and fast rule here. Two cups of cheese makes an especially rich quiche, good for a family brunch or dinner party. Cut it back to a cup or so for a weeknight dinner.

The other fillings just need to be cooked through and fairly dry. Aim for one to two cups cooked ingredients — fewer lets you enjoy the silkiness of the quiche while more make a more substantial meal. Wilted spinach, crisp bacon bits, sauté mushrooms, caramelized onions, and asparagus are all favorites in various combinations.

I’m always surprised by how easily a quiche comes together. I’m still working on my pie-crust skills, but luckily, this is maybe the one dish where the crust is secondary to the filling. That first bite of soft eggy custard makes all other thoughts fade away.

So I ask you, what is your favorite quiche?