Cook 1 1/2 cups macaroni as the label directs; drain and return to the pot. Stir in 2 cups shredded cheddar, 1 cup milk, 1/3 cup each grated parmesan and sour cream, 2 tablespoons butter, 1 tablespoon flour and 1/2 teaspoon each dijon mustard, hot sauce and kosher salt. Transfer to a buttered 1 1/2-quart flameproof baking dish; top with more cheddar and parmesan. Bake at 400 degrees F, 15 minutes, then broil until golden, 2 minutes.
Photograph by Justin Walker
Courtesy of Food Network Magazine