I found this recipe here.
You're going to need:
1 stick of butter (room temperature)
3-4 tablespoons of heavy cream
1 tablespoon of vanilla (I used clear)
2.5-3 cups of powdered sugar
First, put the butter and cream on the bowl (ignore the messy part, I'd made about 5 batches when I remembered to take pictures).
The recipe recommends using the whisk attachment but I like to use the paddle first.
Once the butter and cream are combined, add the vanilla and switch to the whisk.
Once it's all mixed up, you should be able to stand a metal spoon up in it and have it stay, but you should also be able to stir it easily. If you want to dye it, just add food coloring (I use gel) and stir until it reaches your desired color.
The other part I want to do right now is making the filling that will go between the layers. I made a strawberry mash because the adorable little girl asked for it.
All you're gonna need is about a half pound of fresh berries (diced) and a small bag of frozen berries (whole).
Put them in the microwave until the frozen berries are soft. Then find something to mash them with (I used a potato masher).
Once it's mashed, it should look like this:
Tomorrow is going to be the last installment for the Minnie Mouse Cake: Stacking and Icing.