One-Pot Saucy Pasta - Recipook

Ingredients

• 1 pound extra-lean ground beef
• 1 medium onion, chopped
• 3.5 cups water
• 3 cups dried rotini pasta
• 1 (26 ounce) jar spaghetti sauce
• 1 cup chopped red bell peppers
• 1 cup sliced mushrooms
• 1 cup shredded mozzarella cheese
• salt and freshly ground black pepper to taste