Green Bean Casserole

Blanch the beans and shock them

Bring a large pot of well salted water to a hard boil and fill a bowl with ice water. Boil the beans 4 to 5 minutes, until they bend without snapping and turn bright green. Move them straight into the ice water. The cold stops the cooking, which is what keeps them green instead of olive drab. Drain and pat dry.

Heat the oven to 400F (200C)

Butter a 9 by 13 inch baking dish or a 3 quart casserole.

Brown the mushrooms

Melt the butter in a large skillet over medium high heat. Add the mushrooms in one layer and leave them alone for 3 minutes. Stir and cook 5 to 7 minutes more, until the liquid they release has boiled off and the edges are browned. Add the garlic and cook 30 seconds.

Build the sauce

Sprinkle the flour over the mushrooms and stir for 1 minute to cook off the raw taste. Pour in the stock a little at a time, stirring smooth after each addition, then the cream. Simmer 3 to 4 minutes until it coats the back of a spoon. Season with the salt, pepper, and nutmeg. A can of condensed mushroom soup thinned with 1/2 cup milk is the faster swap here, though it tastes like the can.

Fold and fill the dish

Stir the beans into the sauce until coated. Tip into the dish and spread level.

Bake 20 to 25 minutes, onions last

Bake uncovered for 10 to 15 minutes, until the sauce bubbles at the edges. Scatter the fried onions over the top and bake 10 minutes more, until they are deep gold. Adding them at the start burns them black before the middle is hot.

Make ahead. Assemble without the onions up to a day ahead and refrigerate. Add 10 minutes to the covered bake, then top and finish.