Hamburgers - It's in the Bun
Preheat an outdoor grill to high heat, and lightly oil grate.Advertisement
Divide the ground beef into 4 balls, and flatten into patties between sheets of waxed paper. Lay patties onto the grate of the prepared grill. Sprinkle the tops of the burgers with salt. Grill for about 5 minutes per side, or to desired degree of doneness.
While the burgers are cooking, spread each top bun with 1 teaspoon of butter, and spread each bottom bun with 1 teaspoon of mustard. Place the buns onto the grill for just a minute to toast.
Assemble the burgers in this order: Bun, onion, burger patty, cheese, tomato, lettuce, a pinch of salt, and top bun. Spread mayonnaise onto top bun if using.