← All recipes

Sauces · French

Bechamel Sauce

Butter, flour, milk and a little patience: the white sauce behind lasagne and cauliflower cheese.

Hands-on
17 min
Total
17 min
Makes
400 ml (about 1 2/3 cups)
Serves
4

About 3 minutes to melt the butter and cook the flour, 2-3 minutes to whisk in the milk and bring it to the boil, then 5-10 minutes of simmering. Stir the whole time.

  • easy
  • vegetarian
  • mother-sauce
  • basics
  • lasagne

Verified against at least two trusted test kitchens or food-safety guides · Last checked · What this means

Illustration of Bechamel Sauce
Amount
Units

Ingredients

You need: small heavy-based saucepan · whisk or wooden spoon · measuring jug

Contains: milk · wheat

Method

  1. Melt the butter

    Melt 28 g (2 tbsp) butter in a small heavy-based pan over low-medium heat.

    Ready when: The butter has melted and is just starting to foam. It should not brown.

  2. Cook the flour

    Add 15 g (2 tbsp) flour and stir it into the butter. Keep stirring for 2 to 3 minutes to cook out the raw flour taste.

    Ready when: A smooth, pale paste that smells lightly toasty and bubbles gently. It should stay pale; if it turns brown, the heat is too high.

    Otto tried this firstOtto walks off to find the nutmeg and the paste turns brown. That's a different sauce. He starts again and stays at the pan.

  3. Add the milk gradually

    Pour in the 400 ml (1 2/3 cups) milk a little at a time, stirring or whisking constantly. Let each splash blend in smoothly before adding the next.

    Ready when: Smooth and lump-free after each addition; it starts thick and gets thinner as more milk goes in.

    Otto tried this firstOtto dumps all the milk in at once and gets floating lumps. A little at a time, whisking, keeps it smooth.

  4. Bring to the boil

    Keep stirring, getting into the corners and across the bottom, until the sauce comes to the boil.

    Ready when: Bubbles break across the surface and the sauce has visibly thickened. Nothing is catching on the bottom.

  5. Simmer until it coats a spoon

    Turn the heat down and let it simmer gently for 5 to 10 minutes, stirring often.

    Ready when: The sauce coats the back of a spoon: draw a finger through it and the line stays clear.

  6. Season

    Take it off the heat and season with a pinch each of salt, pepper and nutmeg. Too thick? Stir in a little water.

Make ahead, store & reheat

Make ahead
If you're not using it straight away, press cling film (plastic wrap) right onto the surface of the sauce so a skin doesn't form as it cools.
Storage
It's a milk sauce: don't leave it at room temperature for more than 2 hours; refrigerate it within that time.

If something goes wrong

  • Sauce too thick Why: Simmered a little long or reduced too much.
    Stir in a little water until it's the thickness you want.
  • Lumps Why: Milk added too fast or without enough stirring.
    Add the milk gradually and whisk constantly.

Good to know

  • For extra flavour, warm the milk with a bay leaf over low heat before adding it, and finish the sauce with crushed garlic and a second bay leaf.
  • Stir in grated cheese at the end to make a cheese (Mornay-style) sauce, or chopped parsley for parsley sauce; see our Cheese Sauce recipe.
  • Uses: lasagne, cauliflower cheese, fish pie and macaroni cheese.

Safety

  • Thickened sauces can bubble and spit when they boil. Stir with a long spoon, keep the pan handle turned inward, and kids should stir with an adult beside them.