I'm enjoying a nice bowl of Atol Shuco (also spelled "Atol Chuco," and "Atol Shuko") at my beach hotel in the Southeastern-most corner of El Salvador. Shuco is one of the indigenous staples that Salvadorans never stopped eating. It's a massively nutritious dish for two reasons: 1) it's made with "black corn" that's made black by large quantities of polyphenols, so it's highly antioxidant-packed; and 2) it's fermented, so it's loaded with probiotics for healthy gut flora.
For my breakfast, it's got ground roasted aihuashte (also called "aiguashte" or "pepitoria") on top, made from the ground seed (pepitas) of a Salvadoran pumpkin-like squash, which is common when taken for breakfast. Shuco is also eaten with beans and white "pan francés" (basically a white-bread roll) if you have it at night.
People here make it at home. Rural Salvadorans eat it on their way to or from work, purchased from a street vendor.