Sugar Free Cream Cheese Icing
3 blocks of 1/3 less fat cream cheese (aka Neufchatel Cheese), softened
1 pkt sugar free vanilla instant pudding
2% milk (or FF 1/2 n' 1/2)
nutmeg to taste
Whip the cream cheese and SF vanilla pudding mix together. Add enough 2% milk to make it fluffy, then add nutmeg to taste. This makes a thick icing, heavy enough to pipe borders around a cake, but not thick enough to create icing flowers. To make it runnier, you can try using more milk or cut it in 1/2 and add extra milk.
This is the one I found on here. They didn't post any nutritional facts about this though. I love carrot cake too! Have a happy birthday!