The question is far too vague. HK has thousands of great places to eat, which people do indeed know about, so more specificity is required.
I find Open Rice to be useful for information but I would take the ratings with a pinch of salt. They rejected some reviews I submitted which were negative, without challenging my positive ones, so I concluded that there was some bias in the vetting process. I think the Michelin guide, though far less comprehensive, is a better option in terms of objective recommendations.