Hot diggity is right! I really enjoyed the Saigon Fusion dog, which needs no substitutions to be vegan (besides the dog). I generally go with boring hot dog combinations, but the staff member talked me in to this one given that it's their most popular among vegans. He was right, it was really good. The Saigon Fusion dog is Bahn Mi style, so it's loaded with cucumbers, cilantro, and other shredded veggies - all ingredients were tasty and fresh. I'll definitely hit this place up during my next Philly visit.