My mom's birthday is coming up and I wanted to try something new. She loves the taste of smbc, and she loves pistachio. Is it possible to add a box of instant pudding to the smbc? I would also love to make a pistachio cake, but all of my attempts have failed in the past. I might just go with a safe option like vanilla cake :) If you have an amazing pistachio cake recipe you're willing to share, I'd love to try it.
I have no clue about using pudding in buttercream, but when I make it, I use pistachio paste. May not be that easy to fine retail though. Or, I have used the dust from ground pistachios. I toast the nuts, grind them as fine as possible and sift them. The fine dust flavors it pretty well. I've used that mostly to fill pistachio macarons, so it's not smooth, and may not work on the outside of a cake.
As far as cake goes, I think there are several recipes on epicurious.com.
Lorann has pistachio oils. I think the dry powder added to the SMBC as long as you add it a bit at a time would work well. I have mixed it into other things to make pistachio desserts.