Mexican food popularity coincided with the arrival of large numbers of Mexican immigrants after 1950, and have for the most part followed the from and style of what is called "Tex-Mex" food, and amalgam of Northern Mexican peasant food with Texas farm and cowboy fare. Food historians tell us TexMex cuisine originated hundreds of years ago when Spanish/Mexican recipes combined with Anglo fare. TexMex, as we Americans know it today, is a twentieth century phenomenon. Dictionaries and food history sources confirm the first print evidence of the term "Tex Mex" occured in the 1940s. Linguists remind us words are often used for several years before they appear in print. TexMex restaurants first surfaced ouside the southwest region in cities with large Mexican populations. The gourmet Tex Mex "fad" began in the 1970s. Diana Kennedy, noted Mexican culinary expert, is credited for elevating this common food to trendy fare. These foods appealed to the younger generation Only in the last decade has refined, regional Mexican food taken a foot-hold in American cities, reflecting not only the tenets of Tex-Mex cookery by the cuisines of Mexico City, the Yucatan, and other regions with long-standing culinary traditions. Reference Link: http://www.foodtimeline.org/foodmexican.html#aboutmexican

Another great story is about "Nachos". Small restaurant across the border from Texas. Owner's nickname was Nacho. Party of women would come by for his great margaritas. One day they just wanted something light to munch on. Made a platter of what we know now. Everyone loved them and would ask for "Nacho's Special". Years later, Howard Cosell was in town to broadcast "Monday Night Football". He raved about this great appetizer called "Nacho's". The rest is history.

probably around the same time the hispanic population in the US started exploding into the stratosphere. can't eat chinese or italian food everyday, right? mexican cuisine offers tons of variety, is gloriously bad for you and almost infallibly delicious. it should have always been popular, and is still only really popular in a few designated areas (Cali, Texas, Arizona, NM...)