2 tablespoons unsalted butter
2 tablespoons all-purpose flour
1 teaspoon Dijon mustard
1 teaspoon Worcestershire sauce
1/2 teaspoon kosher salt
1/2 teaspoon freshly ground black pepper
1/2 cup porter beer
3/4 cup heavy cream
6 ounces (approximately 1 1/2 cups) shredded cheddar (see note)
2 drops hot sauce
4 slices toasted rye bread
In a medium saucepan over low heat, melt the butter and whisk in the flour. Cook, whisking constantly for 2 to 3 minutes, being careful not to brown the flour. Whisk in mustard, Worcestershire sauce, salt, and pepper until smooth. Add beer and whisk to combine. Pour in cream and whisk until well combined and smooth. Gradually add cheese, stirring constantly, until cheese melts and sauce is smooth; this will take 4 to 5 minutes. Add hot sauce. Pour over toast and serve immediately.
Note: Grate your own cheese for this dish. Already shredded cheeses include potato starch or corn starch to prevent it from sticking. That starch can cause the dish to thicken too much.