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- Add beef, minced onion, parsley, chile powder, salt and black pepper to a large bowl. Mix with your hands until just combined. Gently form beef mixture into 4 equal patties, about 1/2- to 3/4-inch thick. Transfer to a broiler pan or rimmed baking sheet. Cover and refrigerate.
- Add 1 tsp oil to a medium nonstick skillet and set over medium. When oil is hot, add mushrooms and cook until golden brown and soft, stirring frequently, about 8 minutes. Transfer to a small bowl. Add remaining oil to skillet and return to medium heat. Add red pepper and cook for 4 minutes, stirring occasionally. Add sliced onion and continue cooking for 6 more minutes or until vegetables are tender and lightly browned. Add to bowl with mushrooms. Season vegetables with salt and black pepper and stir to combine.
- When you’re ready to eat, preheat broiler to high or a grill to medium-high.
- Place patties under broiler, about 10 inches from heat source, or on a grill. Cook 4 to 5 minutes per side, until meat is no longer pink in center or the internal temperature registers 160 F on an instant-read thermometer. Immediately place 1 slice cheese on each hot burger. (If you want cheese very melted, add it to burgers 30 seconds to 1 minute before end of cooking time.) To serve, layer each bun with 1 lettuce leaf, 1 slice tomato, 1 cheeseburger patty and 1/3 cup vegetable mixture.
- Serving Size 1 cheeseburger
- Calories 320
- Carbohydrate Content 25 g
- Cholesterol Content 65 mg
- Fat Content 10 g
- Fiber Content 4 g
- Protein Content 33 g
- Saturated Fat Content 3 g
- Sodium Content 570 mg
- Sugar Content 5 g
- Monounsaturated Fat Content 0 g
- Polyunsaturated Fat Content 0 g