2 tablespoons butter1 cup mushrooms, sliced1 cup onion, finely-diced1 cup red pepper, diced1 clove garlic, minced1 1/4 pounds ground beef1 1/4 cups Italian-style bread crumbs1/2 cup (about 2 ounces) Wisconsin Parmesan cheese, grated1/2 cup plain yogurt1 egg, beaten1/4 cup ketchup2 teaspoons Worcestershire sauce2 cups (8 ounces) Wisconsin Cheddar Cheese, cubed1 teaspoon salt 1 teaspoon pepper
Preheat oven to 350ºF. In non-stick skillet, melt butter and cook mushrooms, onion, red pepper, and garlic over medium heat until softened, 5-6 minutes.
In large bowl, combine mushroom mixture with the remaining ingredients; mix thoroughly. Place in 9x5-inch loaf pan and bake 50-60 minutes. Drain fat. Let meatloaf stand for 5 minutes before slicing.