Ingredients

  • 2 tablespoons unsalted butter
  • 2 tablespoons all-purpose flour
  • 1/4 teaspoon mustard powder
  • 3/4 cup beer
  • 1/2 cup half-and-half
  • 6 ounces grated sharp yellow cheddar cheese
  • 1 tablespoon horseradish
  • 1 1/2 pounds ground beef, preferably chuck
  • Kosher salt and freshly ground pepper
  • Vegetable oil, for the grill
  • 4 poppy seed rolls, split
  • Tomato slices, for topping
  • 2 tablespoons chopped fresh chives

Method

  • Preheat a grill to medium high.
  • Melt the butter in a medium saucepan over medium heat.
  • Add the flour and mustard powder and cook, stirring, 3 minutes.
  • Whisk in the beer and bring to a simmer; whisk in the half-and-half until smooth.
  • Return the sauce to a simmer and cook, whisking occasionally, until thickened, 3 to 4 minutes.
  • Stir in the cheese and horseradish until smooth; keep warm.
  • Form the beef into four 6-ounce patties, about 3/4 inch thick; press the center of each patty with your thumb to make a 1/2-inch-deep indentation.
  • Season the patties on both sides with salt and pepper.
  • Lightly brush the grill grates with vegetable oil, then grill the patties, indentation-side up, until marked on the bottom, about 5 minutes.
  • Flip and cook until marked and slightly firm, about 3 more minutes for medium doneness.
  • Remove the patties to a plate and let rest 5 minutes.
  • Grill the rolls, cut-side down, until lightly toasted, about 1 minute.
  • Top the bun bottoms with the burger patties, cheese sauce, tomato and chives.
  • Cover with the bun tops.
  • Photograph by Levi Brown