Begin by placing the diced raw white fish in a glass or non-reactive bowl. Pour the freshly squeezed lime and orange juice over the fish, ensuring all pieces are fully submerged. Cover the bowl with plastic wrap and refrigerate the mixture for 30–60 minutes.

Once the marination is complete, carefully drain off most of the citrus juice from the bowl, leaving just a hint of liquid if desired. Add the finely diced red onion, tomato, cucumber, optional jalapeño, and chopped cilantro to the fish. Stir the mixture gently to ensure all ingredients are evenly combined without breaking apart the fish.

Sprinkle in some salt and pepper to taste, mixing thoroughly to incorporate the seasoning. Serve your Citrus Ceviche immediately in bowls, garnished with optional avocado slices or extra lime wedges on the side.