I have been a bit obsessed with mascarpone "cheese" lately. I've used it in both main courses and some dessert-ish dishes. Mixed with some peanut butter, whipping cream, and butter you've got yourself a frosting that won't make you miss sugar. I've made several batches, and I have to use serious self-control to not eat the whole thing at once. I try to balance my carbs, proteins, and fats, or in other words, not eat carbs alone to prevent spikes in blood sugar. So I have no problem laying on a thick layer of this stuff atop banana bread made with almond flour, or atop cinnamon almond flour pancakes with bananas. (I'm on what feels like my bazillionth batch of banana bread, and am getting close to perfecting it...)
1/3 c. butter, softened
1/3 c. mascarpone cheese
1/3 c. peanut butter
2-3 Tb. heavy whipping cream
1 tsp. vanilla
Sweetener to taste (Traditionally, a buttercream frosting is made with powdered sugar, but that's out for me! I use about 15 drops of vanilla stevia. You could use honey, agave, etc.)
Using a mixer, combine the softened butter, mascarpone, and peanut butter. Slowly add whipping cream, vanilla, and stevia and mix on high.
Note: When slathered on hot pancakes, this frosting will be melty! Still delicious, if not as picturesque...