Bake cupcakes from cake mix and let cool, following the directions on the box.
To make the chocolate mousse first heat the butter and chocolate together in a double boiler over low heat. We have found that a double boiler works much better than the microwave, even though the microwave seems quicker! Stir the mixture thoroughly until it is all melted and smooth. I think this is where Eleanor messed up up on our cupcakes, because the chocolate wasn't all quite melted.
Then add the 3 egg yolks and stir completely. Put the mixture in the refrigerator while you whip the egg whites and cream
Whip the egg whites with 1/8 c. of the sugar until stiff peaks form. Set the egg whites aside, clean out the mixer bowl, and whip the cream with the remaining 1/8 c. sugar until soft peaks form.
Fold the egg whites into the chocolate mixture gently, and then fold in the cream. Refrigerate for about half an hour.
Meanwhile, cut out the center of the cupcakes and put the extra cake aside. Once the mousse has chilled a little spoon it into the cupcakes and refrigerate the cupcakes to set the mousse.
To make the frosting mix the cream cheese, sugar, food coloring and mint extract in the mixer. Then slowly add in the cream, whipping until the frosting is smooth and creamy.