My cousin has this recipe that she uses, it's mostly just yogurt, mixed with some butter. It's still thick and decadent feeling but without all that sugar, and it's not that sticky-sweet-gaggy texture. She uses it for her kids' birthdays on a plain yellow cake, and it's very yummy! I don't know that it's 'healthy', considering the butter, but it's definitely 'healthier'. I bet it'd be pure deliciousness with some berries mixed into the cake and used for decoration as well.