In skillet, brown beef and onion;
drain off excess fat. Sprinkle meat with 1/4 tsp salt and
dash pepper. Split chilies lengthwise and remove
seeds; spread open. Lay half of chilies on bottom of a
shallow 1-quart baking dish. Sprinkle with cheese; top with meat
mixture. Arrange remaining chilies over meat. Gradually add milk to flour, stirring
till smooth. Add salt, pepper, eggs and hot pepper
sauce; beat till smooth. Pour over casserole. Bake in moderate oven (350) 45-50
minutes or till knife inserted just off center comes out clean. Pour off excess fat. Cool 5 minutes.