Scottish (Or English) Rarebit - cooking recipe

Ingredients

9 ounces grated cheese (Chesire, Lancashire or Smoked Applewood Cheddar, latter is really good)
6 tablespoons beer
1 tablespoon butter
1 tablespoon Dijon mustard
Worcestershire sauce

Preparation

Heat the cheese, beer and butter over low heat, stirring, until it melts.
Add mustard and a splash of Worcestershire sauce.
Meanwhile, be toasting bread.
Pour sauce over toast and serve.