Method – To prep the shrimp and calamari steep them very briefly (about 2-3 min. each) in steaming hot water. Transfer immediately to an ice bath. To make the dressing, simply combine the juice, zest, onions, garlic, aji, sugar and cayenne. Toss the fish and seafood with the dressing 30 minutes before consumption. To serve, garnish with the avocado and sliced sweet potato (and choclo if you can find it).
Recipe from: http://www.opensourcefood.com/people/GrillAChef/recipes/classic-ceviche-mixto
Changes were made. http://creativecommons.org/licenses/by-sa/3.0/