A great place in the city for pierogie – traditional pierogie, gourmet pierogie, and the best pierogie sandwich (the “PK Stacker” – filled with pierogie, kielbasa, kraut and onions on mustard slathered bread):
They also offer all their pierogie frozen, to go. We were very impressed with our frozen Philly cheese-steak pierogie – they fried up beautifully, were very tasty, and made a reasonably priced dinner at $13/dozen:
Location: Roxborough – not far from Germantown, Wissahican (Garnet Collecting Along the Wissahickon Creek), and Woodmere (Woodmere – Telling the Story of Philadelphia’s Art and Artists).
Tobey says: The Philly cheese-steak ones were my favorite (Kathy’s favorite were the jalapeno/cheddar/potato).
http://www.pierogiekitchen.com/menu/
Other places in the city for pierogie include The Dinner House (Philly Restaurant Review: The Dinner House (Polish Home Cooking)) and Mom Mom’s, a tiny takeout only spot with amazing pierogie and cabbage rolls at 1505 South Street. 
Secrets of Philadelphia 
I make some mean pierogi myself, and I’m happy to see they fry their pierogi correctly – sauteed in butter until a little brown and crispy. All the pierogi I’ve seen in London have been completely deep-fried, and the dough always tastes really tough and stale – not good!
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Pan fried in lots (and lots) of butter! Sometimes I’ve had them lightly fried, so they are still pale and chewy- but I prefer them with a little crunch. But, I’ve never seen them deep fried… must be a British thing – or something they’d serve at the fair, where they deep fry everything.
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I don’t know – they’re made by actual Polish people, but the ones I had in Poland were just boiled and topped with butter (and unadvertised bacon, blech!) so I’m not even sure what’s authentic. Regardless, pan-fried will always be my preferred method!
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