White sauce, also known as béchamel, is an important French sauce with many variations. It is used to hold casseroles together, as a layering sauce in lasagna, and an essential sauce in a gratin. It is also the base for many cheese sauces.

The method is simple: make a roux with butter and flour, then whisk in milk until thickened. Once you’ve mastered this basic version, you can easily build on it with cheese, broth, or cream. Whether you’re layering it into a croque monsieur or spooning it over steamed vegetables, a reliable white sauce is an essential tool for home cooks.

What You’ll Like About This Sauce

Simple and reliable. Just three main ingredients and a few minutes on the stove.

Endlessly adaptable. Use it as-is or turn it into cheese sauce, velouté, or cream sauce.

Essential base recipe. Great for casseroles, lasagna, soufflés, or classic mac and cheese.

Easy to scale. Adjust the butter, flour, and milk ratio for thin, medium, or thick sauces.

Ingredient Notes

Butter: Unsalted is preferred so you can control the seasoning.
Flour: All-purpose flour thickens the sauce and forms the roux.
Milk: Whole milk yields the creamiest results, but any milk will work.
Salt and pepper: Season to taste; use white pepper for a traditional béchamel appearance.

Steps to Make Basic White Sauce (Béchamel)

Melt butter in a saucepan over medium-low heat.
Stir in flour and cook for about 2 minutes, stirring constantly.
Slowly whisk in the milk, continuing to stir to avoid lumps.
Simmer until the sauce thickens, stirring often.
Season with salt and pepper to taste.

Tips for a Smooth White Sauce

Don’t rush the roux—cooking it briefly removes the raw flour taste.
Warm the milk slightly before adding to help prevent lumps.
Whisk constantly while adding the milk for a smooth sauce.
For a thinner or thicker sauce, adjust the butter and flour amounts accordingly.

Recipe Variations

Mornay Sauce. Add 1/2 cup grated Parmesan cheese and stir until smooth.
Cheddar Sauce. Add 1/2 teaspoon ground mustard and 2/3 cup shredded cheddar cheese.
Velouté Sauce. Replace milk with chicken, beef, or vegetable broth.
Cream Sauce. Add 1/3 cup of heavy cream along with the milk.
Extra thick. Use 3 tablespoons each of butter and flour per 1 cup milk for croquettes or soufflés.
Thin sauce. Use 1 tablespoon each of butter and flour per 1 cup milk for light drizzling.

Serving Suggestions

Use as the base for macaroni and cheese sauce or Alfredo-style pasta.
Layer into lasagna or vegetable gratins.
Serve over steamed vegetables or poached eggs.
Add to casseroles for richness and creaminess.
Pair with baked potatoes, chicken, or fish.

How to Store and Reheat

Refrigerate: Store in an airtight container in the refrigerator for up to 4 days.

Freeze? Not recommended, as the texture may become grainy after thawing.

Reheat: Warm gently in a saucepan over low heat, stirring frequently. Add a splash of milk to loosen the sauce if it has thickened.