Open-Faced Burgers with Onion-Mushroom Topping

Ingredients

• 2 teaspoons olive oil
• 1 medium sweet onion, sliced and separated into rings
• 2 (8-ounce) packages presliced mushrooms
• 1/2 teaspoon salt
• 2 teaspoons balsamic vinegar
• 1 1/2 tablespoons paprika
• 1/2 teaspoon salt
• 1/2 teaspoon dried thyme
• 1/4 teaspoon ground red pepper
• 1/4 teaspoon freshly ground black pepper
• 1 pound ground round
• 2 English muffins, split and toasted

Preparation

1. Preheat grill.
2. Heat oil in a large nonstick skillet over medium-high heat. Add onion, and cook for 5 minutes or until golden. Add mushrooms and salt; cook 5 minutes, stirring constantly. Add vinegar; remove mixture from pan. Set aside.
3. Combine the paprika and the next 4 ingredients (paprika through black pepper). Divide the ground round into 4 equal portions, shaping each into a 1/2-inch-thick patty. Coat patties with spice mixture. Grill patties 4 minutes on each side or until done. Place burgers on muffin halves, and top each burger with 1/4 cup onion mixture.