Welsh Rarebit

2 Tbsp. butter
2 Tbsp. flour
1 Tbsp. mustard powder
1/2 tsp. cayenne
3/4 cup strong dark beer, like Guinness
2 Tbsp. Worcestershire sauce
1 lb. Cheddar, double Gloucester or other English cheese
4 to 8 pieces lightly toasted bread

Put butter in a saucepan over medium heat and, as it melts, stir in flour. Continue to cook, stirring occasionally, until golden brown and very fragrant, 3 to 5 minutes. Stir in mustard and cayenne, then whisk in beer and Worcestershire sauce.

When mixture is uniform, turn heat to low and stir in cheese, again stirring until smooth. Remove from heat and pour into a broad container to set (you can refrigerate for up to a day at this point).

Spread mixture thickly on toast and put under broiler until bubbly and edges of toast are crisp. Serve immediately.