Wash the tilapia fillets and cut them into small cubes.
Place tilapia in an bowl, not too deep and cover with lemon juice. (you can use some white vinegar).
Let it rest for about three hours inside the refrigerator until the fish is cooked with the lemon, it will be cooked when it turns white. You can make this step the night before you’ need the ceviche.
When the fish is cooked, you can add the onion, tomato, cucumber and cilantro; Mix the ceviche very well, season with salt and let stand for at least fifteen minutes to mix the flavors.
Serve the ceviche with tostadas or crackers and hot sauce (we use salsa Valentina or Botanera). If you prefer, you can add fresh jalapeño or habanero to the ceviche, instead of sauce.