1 to 1 1/2 lb. ground beef
1 (1 1/2 oz.) env. taco seasoning mix
1/2 c. water
1 unbaked pie shell
1 1/2 to 2 c. crushed corn chips
1 c. (8 oz.) sour cream
1 c. shredded Cheddar cheese

Brown beef, drain fat. Stir in mix and water. Simmer uncovered 5 minutes; sprinkle 1 cup chips in pie shell. Spoon meat mixture over, spoon sour cream over, cover with cheese, top with chips. Bake at 375 degrees for 25 or 30 minutes.