Cafe Podima's blended to order frozen yogurt is no secret. My favourite blend-in is pistacchio.
It's a no-brainer that it's even better with a double order of pistacchio. Turns out there's just the right level of crunchy nutty bits in the yogurt (I think triple pistacchio might push it beyond that point, but not sure...haven't tried yet), and there's a luscious fresh tasting pistacchio flavour. Better yet, there's enough of the nut to impart a tiny hint of the nut-buttery texture to the yogurt.
Minor and easily solvable quibble: somehow the blend wasn't precisely even, the top part had more of the nut than the bottom. Solution: use a spoon to even things out with some gentle mixing before chowing.
Double walnut is next. :)
I had this at the Podima on Cambridge street in Boston; assuming that the branch on Hampshire in Cambridge is similar.