Probably the closest thing Pittsburgh has to a vegan bakery (such things exist, but are rare, and Pittsburgh's vegan scene is doing pretty well).
It's a tiny store, but lots of options and friendly staff, and clearly bustling on a busy afternoon before Thanksgiving. I picked up some cupcakes and a donut, which were really good, but not the most awesome I've ever had - compare Pepples Donuts and Timeless Coffee (both Oakland California) and The Flying Apron (Redmond Washington).
Only 4 stars since labelling and pricing of items could be better, but I'd definitely return for a vegan baking fix.