A tasting menu is a fixed sequence of courses at one price per guest.
It is deliberately not a category. A category holds dishes a diner chooses between; a tasting menu is the opposite proposition, where the chef has already chosen and the price is for the whole sequence. Modelling it as a category would put a per-guest price beside a la carte prices, and the two would mean different things.
To add one: 1. Open Tasting menus in the dashboard. 2. Name it and set the price per guest. 3. Add the courses in order. Each can carry a label ("Amuse-bouche", "Palate cleanser"), the dish name and a description. 4. Leave a course as a chef's surprise if you do not want to name it. The menu says so, rather than showing a gap that reads as a mistake. 5. Add a wine pairing price if you offer one. It is quoted separately, as on any real menu. 6. Set a minimum number of guests and the notice the kitchen needs, if either applies. 7. Note any dietary versions you can prepare on request.
The course count is never typed: it is the number of courses you added, so the headline can never disagree with the list beneath it.
Diners find it behind the More button on your menu.