I found the official website https://www.nyctourism.com/restaurant-week slow and tedious to navigate, so I hacked together a fast, filterable map to showcase the participating NYC restaurants during Restaurant Week.
It's in pure HTML, CSS, and JS, and it uses Leaflet for mapping and a utility JS file for the searchable multi-select input. If you're interested, check out the unminified source code by right-clicking and selecting "view source". The full source is available here: https://github.com/Blue9/restaurant-week.