Béchamel Sauce

The base white sauce for lasagna, gratins, and croque monsieur. Equal parts butter and flour make the roux; milk brings it together.

#Steps

1. Melt the butter in a saucepan over medium heat
2. Whisk in the flour and cook for 1–2 minutes — the roux should smell nutty but stay pale
3. Add the milk in a slow stream, whisking constantly to avoid lumps
4. Simmer gently, stirring, until the sauce coats the back of a spoon
5. Season with salt, white pepper, and a pinch of nutmeg

#Variations

Thicker or thinner Use less milk for a stiff sauce (croquettes, fillings) or more for something pourable (lasagna layers).

Mornay Stir in grated Gruyère or Parmesan off the heat until melted — good for mac and cheese or gratins.

Nutmeg and bay A bay leaf in the milk while warming adds depth; fish it out before adding to the roux.