Vitello tonnato in T.O.?
I just did a quick google search with the "vitello tonnato toronto" and it picked up a bunch of different mentions of it on menus. The risk is that the menus have changed since they were posted on the web but might be a good starting point. Included in the results were Sotto Sotto:
Sotto Sotto Restaurant
116 Avenue Rd, Toronto, ON M5R2H4, CA