Excellent bakery. I've ordered two cakes from here in the past as well (one I just decided to get when walking into the bakery on my dad's birthday) and one for my sister's baby shower - and the cakes did not disappoint. They were also beautifully decorated. We've gotten cookies and donuts from here and from the location on Washington Road in Mt. Lebanon - never had anything that wasn't delicious!!
Potomac location does accept credit/debit cards, but I believe you have to have a $10 minimum to use a card to pay; just something to note. I'm not sure if that policy is the same at the Mt. Lebanon store. Don't let that deter you!!