I always make this filling for a cake that my family likes, but I want to cover the whole cake this time, and I want it to crust. How would I do that without changing the taste too much?

3 sticks margarine
1 1/2 cups conf sugar
2 tsp vanilla sugar
3 egg yolks
juice of 1 1/2 lemons

Cream margarine and sugars. Add one yolk at a time. Mix for 5 minutes, and only then add lemon juice. Mix to combine.

Any help would be appreciated!!

Increase the powdered sugar to make it crust. It's the proportion of sugar to fat that determines if a frosting will crust.

That's what I read, I just wanted to make sure I understood. Slightly (okay, maybe not slightly) sleep deprived). Thanks so much.