Bekta is probably the most consistent- innovative yet not over the top or pretentious- choice.
Not cheap but worth it; balance that out by saving money on shawarma- Marroush, 309 Elgin St- down the stairs- often referred to as the Shawarma Nazi (after Seinfeld's soup nazi); Pho is also very good and cheap in Ottawa- many places on Somerset- the Vietnam Palace is a little nicer than most- and no MSG.
819 Somerset St W, Ottawa, ON K1R6R4, CA
Try Sweetgrass aboriginal bistro
The Wellington Gastopub
Have a Shwarma or go for some poutine too if you get a chance.
Beavertail pastries in the Market are also a local specialty.
108 Murray St, Ottawa, ON K1N5M6, CA
85 Murray St, Ottawa, ON K1N5M5, CA