A velvety Muenster and light beer cheese dip great for game day, with pretzel bites, or served with toasted rye triangles. Don't expect it, but if there are leftovers, this snappy cheese sauce doubles as a cracker spread when chilled.
Heat butter in 4 quart sauce pot over medium heat just until melted. Add the sliced green onion and minced garlic. Stirring often with a wooden spoon, slowly cook until soft, about 2 minutes. Immediately sprinkle in flour. Continue to cook and stir over medium heat until flour mix is lightly browned and smells like baked piecrust, about 1-2 minutes. Reduce heat slightly, slowly whisk in milk then lager, a little at a time, stirring well to remove lumps between each addition. Whisk in ground mustard powder, sugar, Worcestershire sauce, salt, black pepper, and cayenne pepper. Increase heat, and simmer until flour is cooked and the sauce is velvety, about 5-8 minutes; stir and scrape sides and bottom of pot constantly. Reduce heat and add cheese about ½ cup at a time, stirring constantly, and waiting until each batch is fully melted before adding the next. Remove from heat. Serve immediately with toasted rye bread triangles, pretzel bites, sausage, or sliced vegetables. Serves 8-10 as dip (about 2 cups)