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Learn to cook / Sauces

How to make white sauce (béchamel)

Quick answer

Make a light roux from 25 g butter and 25 g flour for 1–2 minutes. Whisk in 400–500 ml warm milk a little at a time. Simmer 5–8 minutes, stirring, until the sauce is glossy and coats a spoon.

These steps assume

  • Butter and flour are 1:1 by weight for a light roux.
  • Milk is warmed before it is whisked in.
  • The sauce is stirred regularly while simmering so the base does not scorch.
  • The goal is a classic béchamel that coats a spoon.

This is what it should look like

Smooth pale béchamel coating the back of a spoon

Smooth pale béchamel coating the back of a spoon

Pale blond butter-flour paste ready for milk

Pale blond butter-flour paste ready for milk

What you need

  • 25 g butter
  • 25 g all-purpose flour
  • 400–500 ml milk
  • Small heavy-bottomed saucepan
  • Whisk
  • Salt, pepper and optional nutmeg

Step by step

  1. 1

    Warm the milk in another pan or the microwave until hot to the touch — not boiling.

    • Equipment: Second pan or microwave-safe jug.
    • Heat: Low to medium heat.
    • Time: 2–4 minutes.
    • Looks like: Milk steams lightly; no skin if you stirred while heating.
    • If it goes wrong: Milk boiled over — skim gently and use it still warm.
    • Done when: The milk is warm and ready for the roux.
  2. 2

    Melt the butter, sprinkle in the flour and whisk 1–2 minutes until smooth and light blond without browning.

    • Equipment: Saucepan and whisk.
    • Heat: Medium heat.
    • Time: 1–2 minutes.
    • Looks like: The paste smells lightly nutty, not of raw flour, and is still pale.
    • If it goes wrong: Roux browned — for béchamel, start again; brown colour changes the flavour.
    • Done when: Light roux ready for milk.
  3. 3

    Whisk in the warm milk a little at a time until smooth. Add the rest and bring to a gentle boil while stirring.

    • Equipment: Whisk.
    • Heat: Medium heat.
    • Time: 2–3 minutes.
    • Looks like: No flour lumps; the sauce is even, still slightly thinner than finished.
    • If it goes wrong: Lumps — take off heat, whisk or strain; add milk more slowly next time.
    • Done when: Milk is incorporated without large lumps.
  4. 4

    Simmer the sauce, stirring, until it coats a spoon. Season with salt, pepper and optional nutmeg.

    • Equipment: Spoon.
    • Heat: Low to medium — gentle simmer.
    • Time: 5–8 minutes.
    • Looks like: Sauce is glossy, smells of milk and butter, and leaves an even film on the spoon.
    • If it goes wrong: Scorched base — change pans without scraping the burnt layer; keep heat lower next time.
    • Done when: White sauce is smooth, glossy and seasoned.

If it doesn't turn out as expected

  • Lumps

    milk too cold or added too fast; whisk off heat or strain.

  • Raw flour taste

    undercooked; simmer a few more minutes while stirring.

  • Scorched base

    heat too high or stirred too rarely.

  • Too thick or thin

    adjust with warm milk or a longer simmer.

Food safety

Hot milk and sauce can scald. Keep the pan steady and stir away from your face.

When it's done: The sauce is smooth, glossy and white to cream-coloured with no lumps or raw flour taste.