As a chowhound and Asian-Canadian growing up in Toronto (though long since gone), I note that there hasnt really been a good description on this site of Chinatown restaurant evolution in our fair city. I welcome others to chime in to fill the gaps or describe earlier or later times.
I recall in the sixties, Chinatown was focused within a couple of blocks of Dundas and Elizabeth. There were 3 major restaurants frequented by Chinese: Sai Woo, Kwongchow (both on Elizabeth), and the Golden Dragon (on Dundas). Lichee Gardens and Nanking (also on Elizabeth) were tad more expensive and catered to westerners. Sai Woo and Golden Dragon were primarily for dinners or wedding banquets. Kwongchow was our place for dim sum, then ordered and not wheeled in carts. There may have been half dozen choices: har gow (shrimp dumplings), sui mai (pork dumplings), steamed pork buns, custard tarts and a couple of others. The har gow were stuffed with pork filling with a little shrimp. Sunday, every Chinese family that could come was there as it was the only day off for most. Also in the neighborhood was a coffee shop called Lees Grill that served apple turnovers and butter rolls as well as standard diner food (hot beef sandwich, burgers). There was also a basement place on Dundas with green tiles (whose name I never knew) that mostly catered to gambling men. Added to this was the Great China a little later and further west on Dundas but still not as far as University Ave.
In the 70s, major immigration from Hong Kong increased the demand for real Cantonese food. More authentic restaurants began to open. The first place that offered the diverse dim sum that we see now was Mambo (Treasure) and I recall waiting for several hours for a table while my mother went to Church. This was followed by Pink Pearl. The other change was the emergence of a second Chinatown centered at Dundas and Spadina. Restaurants such as Moon Villa and the International sprang up. Also, the Dragon Mall on Spadina was a harbinger of future growth in the suburbs. The increase of Taiwanese in the city led to other Chinese cuisines becoming available and the pioneer in this was Pauls Deep Sea Shantung, the first Szechuan restaurant located on Queen (not even in a Chinatown!) This was followed by Peking, Hunan and even Swatow mostly located on Spadina.
The 80s saw a gradual shift away from the downtown as second generation Chinese began moving in large numbers to the suburbs. While the Spadina Chinatown continued to thrive with restaurants such as Pot of Gold, Chinatowns with malls sprang up in Scarborough, Markham, Richmond Hill and the easy parking and clean surroundings made this the desired location for new restaurants. A fourth Chinatown also sprang up on East Gerrard Street for newly arrived and less well heeled immigrants. This area offered Chowhoundish holes in the wall for noodles or congee. The original Chinatown seems sad and desolate now when I walk through it, filled with memories of Golden Dragons chicken wings, Sai Woo's chow mein, or Kwongchows limited but delicious dim sum.