Welsh Rarebit Recipe

Traditional Welsh Rarebit recipe:
Ingredients:
2 tablespoons butter
2 tablespoons all-purpose flour
1 cup beer (or milk/stout for variation)
1 cup grated cheddar cheese (preferably a strong, sharp variety)
1/2 cup grated mustard cheese or other tangy cheese (optional)
1 teaspoon mustard (English mustard or Dijon work well)
1/2 teaspoon Worcestershire sauce
Salt and pepper to taste
4 slices of bread (toasted)
2 egg yolks (optional, for richness)

Instructions:
1.Melt butter in a saucepan over medium heat.
2.Add flour and whisk to form a smooth paste (roux). Cook for 1 minute.
Gradually add beer, whisking continuously to avoid lumps. Bring to a simmer.
3.Reduce heat to low and add cheddar, mustard cheese (if using), mustard, Worcestershire sauce, salt, and pepper. Stir until cheese melts and the mixture is smooth.
4.If using egg yolks, beat them lightly and temper with a little of the warm cheese mixture. Then, stir the egg yolk mixture into the cheese sauce.
Toast the bread slices and place them on a baking sheet.
Spoon the cheese mixture over the toasted bread, covering it evenly.
Place under a Grill until golden brown and bubbly.
Serve immediately.
Enjoy your traditional Welsh Rarebit!