Your menu is the absolute most important thing not only on your website, but of your entire web presence. But simply uploading that giant PDF to your website won't do you much good.

Ideally, you want to put an HTML (aka text) menu on your website, not a 50MB PDF that takes customers a year to download. This means creating a dedicated page (or several pages) for each menu that you have. The benefits to this are many:

1. improved page loads
2. improved user experience
3. persistence of breadcrumbs/links back to site
4. reduced bounce rate
5. more congruent customer experience
6. ability to create interactive menu
7. ability to use call-to-actions throughout menu (call or make reservation links)

Another great idea is to include pictures along with your food. Potential customers are much more likely to get excited about a picture of one of your star dishes than a short textual description (words can only be so succulent).

While implementing all of these fancy ideas along with your menu will certainly help it convert, don't overlook this simple fact: simply migrating your existing pdf to a plain-looking page on your website will be an improvement.