Yes, you can reheat white sauce (béchamel). Refrigerate it within 2 hours of making it, use it within 3 to 4 days, and reheat it gently, whisking in a splash of milk, until it’s smooth and steaming hot (165°F / 74°C).
White sauce thickens a lot in the fridge and can form a skin. Both are normal and easy to fix.
How to store it
- Press plastic wrap onto the surface of the sauce before chilling it. This stops a skin forming.
- Use a covered container and refrigerate it within 2 hours.
- Freeze it for longer storage, up to about 3 months. Flour-thickened sauces freeze better than you might expect, though they may look a little grainy at first.
How to reheat it
On the stove (best):
- Put the sauce in a pan over low to medium-low heat.
- Add 1 to 2 tablespoons of milk per cup of sauce.
- Whisk constantly as it warms. Add more milk until it’s the thickness you want.
- Heat it until it’s steaming and gently bubbling.
In the microwave:
Heat it in a covered bowl in 30-second bursts, whisking between each, and add milk as needed.
Fixing problems
| Problem | Fix |
|---|---|
| Too thick | Whisk in warm milk a little at a time |
| Lumpy or grainy | Whisk hard, or use a stick blender |
| Separated (cheese sauces) | Take it off the heat and whisk in a little cold milk. Avoid boiling cheese sauces hard |
| Scorched on the bottom | Don’t scrape it. Pour the good sauce into a clean pan |
Quick answers
Can I reheat white sauce more than once?
It’s best to reheat only what you’ll use. Each reheat dulls the texture.
What about lasagna or a gratin made with white sauce?
Reheat the whole dish, covered with foil, at 350°F (175°C) until it’s hot in the middle.
Source: USDA Food Safety and Inspection Service, Leftovers and Food Safety.