Hollandaise Sauce
Hollandaise sauce is a mixture of egg yolk, melted butter, and lemon juice (or a white wine or vinegar reduction). It is usually seasoned with salt, and either white pepper or cayenne pepper. It is well known as a key ingredient of eggs Benedict, and is often served on vegetables such as steamed asparagus.
Source: Wikipedia
Recipes
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How to Make Hollandaise Sauce - Jessica Gavin
Homemade hollandaise sauce adds a touch of elegance to any meal. It's a warmed egg and butter emulsion made quickly on the stovetop. This rich and velvety sauce is a breakfast staple to drizzle over eggs benedict or savory poultry, seafood, and vegetables...