1 lb. ground beef
1/2 c. chopped onion
1 envelope taco season mix

Brown beef with onion, drain. Stir in season mix. Place in 9 inch pie plate.

Mix together:

1 1/4 c. milk
3/4 c. Bisquick
3 eggs
1/2 c. shredded cheddar cheese

Beat together and pour over meat mixture. Bake at 400 degrees for 25 minutes. Top with 1/2 cup cheese and bake 5 minutes longer. Knife should come out clean. Cool 5 minutes. Serve with shredded lettuce, chopped tomatoes and sour cream.