"Nacho toppings" refers to the various ingredients that can be added on top of a plate of nachos, such as cheese, salsa, Guacamole, sour cream, and jalapeños, to enhance their flavor. Full definition
Serve nachos topped with cabbage mixture and pickled jalapeños. (bonappetit.com)
Take roasted cauliflower, which I already love on its own, and top it with taco meat, cheese, and all of your other favorite nacho toppings. (detoxinista.com)
Serve nachos topped with tomatillo avocado salsa, pico de gallo, sliced jalapeño, and radishes. (bonappetit.com)