Foothill Farms White Sauce Instant Base Mix is a basic white sauce that is used as the base for other classic sauces. This classic blend of butter, flour and milk adds a rich and creamy quality to a variety of dishes. Preparation is quick and easy. Just add hot water (no boiling) for perfect, consistent sauce every time. White sauce is the starting point for other classic sauces such as mornay, veloute, and cheese sauces.