David Chang's Momofuku Noodle Bar empire is built around ramen. It's what most people order there. But the real star on their menu is actually the PORK BUNS! These are by far the best buns/baos in Toronto - and my absolute faves. I have yet to find tastier ones in the city. They just never compare. These little Asian handheld pillowy goodies are so flavourful and...just melt in your mouth.
When I lived in Montreal, every time I visited either NYC or Toronto I would always make a pit stop at Momofuku for some pork buns. I like to come here for a quick bite/snack - sit at the bar, order some pork buns and a beer, and just relax.
Other items that I recommend: The Roasted Rice Cakes (great snack - spicy good), The Very Extremely Spicy Noodles (really good - BUT BE WARNED: IT IS EXTREMELY SPICY. FOR REAL!!)
P.S. The ramen is ok - nothing spectacular. For ramen cravings, I recommend going elsewhere in the city (e.g. Sansotei), which are very close to the authentic Japanese experience!