Hi Jessicakjj. I made icing once for a chocolate cake using a recipe I found that uses sugar free, instant pudding. I used chocolate pudding. It was okay, but was not the thick and fudgy type of icing I prefer. A cream cheese frosting might be good or a simple chocolate ganache of melted bakers chocolate, Splenda, and a little water mixed together and poured over the top.

(By the way, one T of natural peanut butter in the cake batter is an interesting variation.)

1 pkg Jello® Sugar Free Vanilla pudding*
1 8 oz. container mascarpone or cream cheese
1 cup heavy cream
3 pkts Splenda®
Half 'n Half (to thin to make spreadable if needed)

Whip mascarpone or cream cheese in food processor or with electric mixer until smooth. Add cream and mix again briefly. Add pudding mix and Splenda® and mix well. Add Half 'n Half in 1/2 teaspoon amounts if needed. Makes enough to frost 32 cupcakes (2 batches) and will store in fridge or can be frozen. This recipe can also be spread in fudge pan, frozen and cut in squares as a treat.
* Chocolate Jello® pudding can be used for Chocolate Frosting or fudge.