Pasteur is the best Vietnamese restaurant in Toronto.
The pho broth is very flavorful without being too oily. If you like things spicy, request satay in your pho and you will be treated to the pinnacle of pho delights. The rare beef is fresh and nicely sliced. Get a large if you are very hungry and your hungry will be satiated quite nicely.
The rice dishes are also very good. My particular favourite is the grilled beef with rice (I often opt for an additional fried egg on top). The beef is nicely grilled, with subtle seasonings and garlic. The rice is generously piled on the plate.. Drizzle the fish sauce over the dish and it transforms into an exquisite masterpiece revealing itself with every bite.
The fresh fruit shakes are also noteworthy. Try the green bean, pennyleaf, and coconut.