Yes, Donovan's really does have the best cheeseburger in the city. (My experience is limited to the Woodside version.) Jim, and everyone else who claimed it as such, is correct. No question there.
My argument is about the fried onions. Every Leffian Donovan's recommendation here contains the added note that one -must- order this burger with fried onions. Which, the first time I had it, I did. They are very, very good fried onions. But I don't think they belong on this particular burger.
What is notable about this burger? It is soft, it is moist, it is rich, and, because of the quality of the meat, it is slightly sweet (in that beefy sweetness sort of way). What are the fried onions like? They are soft, moist, rich, and slightly sweet.
The fried onions are redundant. They mirror the instrinsic qualities of the burger in ways which are confusing. When I arrived at this idea, I decided that -raw- onions would be what this burger requires. I have since confirmed it. Raw onions provide crunch and bitterness that perfectly complement this best of all possible burgers. You should order your Donovan's cheeseburger with raw onions.
I realize that this is a very big issue, something that will not be resolved with one post.
So, in order to do further research, I have moved to the neighborhood.
I've just signed a lease on an apartment on 55th Street. Donovan's is my new local.
Of course, Donovan's burgers aren't the only reason I've relocated. A while back some poster promised a full report on Sunnyside Irish bars. That never happened, so I realized I have to do it myself.
At present, Tailors Hall and J.J. Gilligan's are neck-and-neck in my affections, but there is clearly much more work to do.
Expect further reports.