Muenster is a semi-soft cow's-milk cheese with a pale interior and a washed, orange-tinted rind, from the Alsace region of France; it takes its name from the town of Munster in the Vosges mountains, where Benedictine monks are traditionally credited with first making it.
The wheels are washed repeatedly with a brine solution during aging (typically 4-8 weeks), which encourages the growth of Brevibacterium linens on the surface. That bacteria produces the cheese's characteristic orange rind along with its pungent aroma and mild, salty, slightly nutty flavor; the paste itself stays soft and creamy.
Muenster melts smoothly, which makes it a common choice for grilled cheese sandwiches and other melted-cheese dishes; its mild flavor also makes it a popular table cheese with crackers or bread. American Muenster, widely sold in U.S. supermarkets, is a milder, often rindless approximation of the French original and should not be assumed to be the same cheese: it is typically younger, blander, and made without the same washed-rind aging.