The cupcakes that I bought at Oh Sweet Mama Vegan Bakery are probably the best vegan cupcakes that I have ever tasted. The strawberry shortcake cupcake had a sweet, vanilla-like cake flavor and topped with faux whipped cream and strawberry slices. The whipped cream didn't taste at all like soy - it tasted amazingly like the real thing.
I also tried the cardamom rosehip cupcake, which was indescribably good. Seriously, I can't find words to describe the taste because it was unlike anything I had ever eaten before, but I would definitely drive back to Northampton for another one if only it wasn't so far away.
The vegan scones from Oh Sweet Mama were also very good - they came in flavors like ginger and maple walnut and were dry (as scones should be!) without being overly dense (as some vegan baked goods tend to be).
I could go on and on about this place. If you're ever in the Northampton area, it's definitely worth stopping by.