To thin hollandaise sauce that's too thick, whisk in a teaspoon of warm water at a time until you reach the desired consistency. Be careful not to add too much water, as this can make the sauce too thin or break it.
Hollandaise sauce can become thick due to overcooking, too much butter, or cooling down. The key to thinning it is to gently re-emulsify the sauce with a small amount of warm water. Here's a step-by-step guide:
Prepare Warm Water: Have a small bowl of warm (not hot) water ready. The temperature should be similar to the hollandaise sauce.
Add Water Gradually: Add one teaspoon of warm water to the hollandaise sauce.
Whisk Vigorously: Immediately whisk the water into the sauce using a wire whisk. Whisk until the water is fully incorporated and the sauce starts to thin.
Check Consistency: Evaluate the consistency of the sauce. It should be thick enough to coat the back of a spoon but thin enough to pour easily.
Repeat if Necessary: If the sauce is still too thick, repeat steps 2-4, adding one teaspoon of warm water at a time and whisking thoroughly after each addition. Be patient and add the water slowly to avoid breaking the emulsion.
If your hollandaise sauce breaks (separates), try whisking an ice cube into a separate bowl, then slowly drizzling the broken sauce into the cold water while whisking constantly. The rapid temperature change can sometimes help re-emulsify the sauce.