Mexican Mac and Cheese

Name: Mexican Mac and Cheese
Prep time: 5 min
Cook time: 25 min
Total time: 30 min
Cuisine: American, Mexican, Latin American
Ingredients: 1 pound extra-lean ground beef (95% lean); 1 large onion, chopped; 1-1/4 teaspoons chili powder; 1 teaspoon dried oregano; 1/4 teaspoon salt; 1 can (14-1/2 ounces) diced tomatoes, undrained; 1 can (8 ounces) tomato sauce; 1 cup fresh or frozen corn; 1/2 cup water; 2/3 cup uncooked elbow macaroni; 1/2 cup shredded reduced-fat cheddar cheese