Preheat oven to 350 degrees F.
Arrange roast beef evenly over the four slices of bread. Carefully place the sandwiches directly onto the baking rack in the oven, and bake for 10 minutes. (You can put them on a baking sheet if you prefer, but bread will not be crisp.)
While sandwiches are baking, melt butter in a skillet over medium heat. Stir in flour until smooth, and then slowly pour in beer, stirring constantly to keep sauce smooth. Add milk, stir, and bring to a simmer. Add cheese, and stir until melted.
Taste sauce and add a pinch of salt and a little freshly ground black pepper to taste. Stir in additional 2 tbsp. milk.
Place toasted sandwiches on plates, and immediately spoon cheese sauce over each one. Serve with a fork and knife, and dig in!
This cheese sauce sets up quickly when cooled, so serve immediately.
- Prep Time: 10
- Cook Time: 10
- Category: Main