Tacos are quick meals.
Tacos are amazing! my favorite food! Although  origins of the taco are not precisely known, and etymologies for the culinary usage of the word are generally theoretical.
Tacos are also a fast food in USA.
Yes. they have taco bell. Taco Bell is an American chain of fast food restaurants based out of Irvine, California... a subsidiary of Yum! Brands; I like taco bell!!
Taco can be used with condiments of mild and spicy sauces.
Yes they can. This meaning of the Spanish word "taco" is a Mexican innovation, but in other dialects "taco" is used to mean "wedge; wad, plug; billiard cue; blowpipe; ramrod; short, stocky person; [or] short, thick piece of wood; funny!!