"The classic thick, juicy cheeseburger burger meets the iconic topping of grilled green pepper and onion draped in a mantle of sharp cheddar."
1 pound ground beef, preferably 85% lean
1 teaspoon coarse kosher salt
½ teaspoon ground pepper
1 tablespoon extra-virgin olive oil
½ medium onion, sliced
½ sweet bell pepper, sliced
4 ounces Cabot Extra Sharp Cheddar, cut into 12 slices
4 hamburger buns, toasted if desired
Preheat Big Green Egg or other grill for medium-hot direct grilling and place a 12-Inch Skillet on the grates to preheat. The temperature sensor on the lid should read a constant 400–450°F.
Form beef into 4 burger patties. Sprinkle all over with salt and pepper.
Swirl oil in the skillet. Layer in the onion and peppers, and place skillet on the hot grill surface, slightly to one side. Cook until the vegetables are sizzling in the oil, about 3 minutes. Stir the vegetables and continue cooking, stirring often, until they are soft, about 12 minutes.
When there is about 4 minutes left for the vegetables, place the burgers on the grill next to the skillet. Cook 4 minutes on the first side, rotating a quarter turn halfway through.
Scrape peppers and onions to one side of the skillet with a spatula.
Flip the two burgers onto their uncooked side and place on the open side of the skillet. Use tongs or the spatula to top the burgers with half of the vegetable mixture, dividing evenly. Repeat, clearing spots and topping the remaining two burgers. Top each burger with three slices of cheese each.
Cover the Big Green Egg and let cook until the burgers are grilled to desired doneness and the cheese is melted, 4–6 minutes. Serve on buns.