Cook ground beef and onion until brown. Drain fat and add garlic, chili powder, salt, pepper and water. Simmer uncovered for 10 minutes, stirring occasionally. Pour 1/2 cup picante sauce in greased 9x13 pan. Arrange half of tortillas over sauce to cover bottom. Pour 1/2 cup picante evenly over tortillas. Spoon in beef mixture and top with sour cream. Sprinkle on half of cheese. Arrange remaining tortillas over cheese, overlapping as necessary. Spread remaining picante sauce over tortillas and top with remaining cheese. Loosely tent with foil and bake for 40 minutes at 375. Remove foil and bake 5 more minutes. Enjoy....Ole!