Homestyle Stuffed Peppers

INGREDIENTS

• 4 green bell peppers, tops and seeds removed
• 1 1/2 pounds lean ground beef
• 1 cup cooked white rice
• 1 egg, lightly beaten
• 1/4 cup finely chopped onion
• 1/2 cup Italian-style bread crumbs
• 1/4 teaspoon salt
• 1/4 teaspoon black pepper
• 1/2 teaspoon garlic powder
• 1/4 cup grated Parmesan cheese
• 1 (28 ounce) can tomato sauce
• 1/4 cup white vinegar
• 2 tablespoons grated Parmesan cheese