This authentic Yucatan-style ceviche with avocado tastes like summer

About the recipe
Ceviche refers to fish that has been “cooked” by the acidity of the lime juice. No actual heat transfer takes place, but the acid denatures the proteins of seafood enough to mimic the texture of cooked fish.
You’ll want to find the freshest fish of the highest quality available, preferably sashimi-grade. Bass, snapper, grouper and halibut are all great choices. This is not the time to cut corners with bottled citrus juices. Buy your own limes and juice them. The difference will be noticeable.
Serves: 4
Ingredients
12 ounces firm, white fish fillets (see note), cut into 1/2-inch pieces
1/2 red onion, finely diced
1 cup fresh lime juice
2 oranges, segmented
2 Roma tomatoes, seeded and diced
1 bunch cilantro, roughly chopped
1 avocado, halved, seeded, and diced
2 jalapeno peppers, seeded and minced
2 tablespoons extra-virgin olive oil
Kosher salt
Corn tostadas or tortilla chips, for serving
Instructions
In a large bowl, combine the fish, onion and lime juice. Refrigerate for 30 minutes, then remove the fish and onion from the lime juice; discard the juice.
Stir in the oranges, tomatoes, cilantro, avocado, jalapeno and olive oil. Season to taste with salt and serve with the tostadas or chips.