First of all is your oven calibrated correctly? If it is try this, either buy
the Wilton Bake-Even strips to go around your cake pans to insulate them or cut
lengths of old towels long enough to go around your pans and wide enough to
fold over 3 times. Wet thoroughly with water and wrap around pans and secure
with large safety pins. Bake.

Decorator Icing

1 c. margarine
1 lb. powdered sugar
1/2 c. flour
1/2 t. salt (really)
1 t. good quality vanilla
1/2 c. (adjusted to desired consistency) water or milk

Cream margarine and flour,salt, and 1/2 the sugar, add liquid and and vanilla
beat about 5 minutes or until the sugar dissolves and it loses its grainy
"bite". Adjust the liquids to suit the consistency you need and the humidity in
the air.