Preheat oven to 350 F. Cook pasta shells in salted, boiling water until done; drain. Brown ground beef and drain. Combine Picante sauce, water and tomato sauce. Stir 1/2 cup sauce mixture into meat along with chilies and one-half of cheese and one-half of onions. Pour half of remaining sauce mixture into the bottom of an oblong baking dish. Stuff shells with meat mixture and arrange in dish. Pour remaining sauce mixture over shells. Bake covered 30 minutes. Top with remaining cheese and onions. Bake uncovered an additional 5 minutes. Serve with Mexican rice and beans.
Cajun Country -- New Iberia, Louisiana