How do you stop a sauce getting skin?

During cooking:

* Keep it moving: Stirring or whisking the sauce regularly disrupts the surface and prevents a skin from forming.

* Cover it: Use a tight-fitting lid or plastic wrap pressed directly onto the surface of the sauce. This prevents air from reaching the surface.

* Add a thin layer of oil: A thin layer of oil on top of the sauce will act as a barrier against air and moisture loss.

* Use a simmer: Simmering the sauce gently rather than boiling it helps reduce evaporation and skin formation.

After cooking:

* Store in airtight containers: Transfer the cooled sauce to an airtight container to prevent exposure to air.

* Refrigerate with a thin layer of oil: Add a thin layer of oil to the surface of the sauce in the container before refrigerating.

Specific Tips for Different Sauces:

* Tomato-based sauces: Adding a teaspoon of sugar or a splash of vinegar can help prevent skin formation.

* Cream-based sauces: Adding a splash of heavy cream or a knob of butter can help create a barrier against skin.

* Dairy-free sauces: Adding a tablespoon of oil or a sprinkle of cornstarch can help prevent a skin from forming.

Important Note: Some sauces are naturally prone to forming a skin, such as béchamel sauce. It's important to note that a thin skin is usually harmless and can be easily whisked back into the sauce. However, a thick skin may indicate that the sauce has been overcooked or not stored properly.