I'll make a long story short and say that GBK is currently my favourite place to get a burger in Toronto, and has been for a long time now.
They have a burger du jour all week long as well as a poutine of the day. If that doesn't tickle your fancy you can always choose from the many menu options.
There are many burger and poutine combinations. I make my way here often to satisfy my craving for a good meat patty cooked the way I like it.
Must-try items:
Voodoo Burger
Montreal Poutine
Feta, Cheddar & Swiss Poutine
Most of the time I dine in but they also do takeout very well. They also deliver in the Leslieville area, which is a great excuse to move into this neighbourhood, not that you needed one. Seriously, try these burgers. They're awesome.