Lay the fillets out flat on a cutting board. Instead of cutting straight down across the "grain" of the meat, slice bite-size pieces diagonally down, slanting with the grain of the meat. This will produce a more open meat surface that the lime juice can penetrate.
Squeeze the limes into a bowl and add the tilapia pieces, making sure they are completely soaked in the juice. The fish will begin to turn white. Add the cilantro, aji limo, salt and garlic, mixing thoroughly.
Plate the fish on a bed of lettuce. Then add the onions to the bowl of left over juice (the favorite part of ceviche for many). Briefly swish the onions in the juice and then pile them on top of the fish, drizzling the remaining juice on the ceviche heap. Serve with boiled sweet potatoes and choclo.
Warning: Consumption of raw or undercooked fish may substantially increase the risk of foodborne illness.
This recipe was provided by a chef, restaurant or culinary professional and may have been scaled down from a bulk recipe. The Food Network Kitchens chefs have not tested this recipe, in the proportions indicated, and therefore, we cannot make any representation as to the results.