Trim and pat dry 1 cup sashimi-grade ahi or white fish. Dice into 1/2-inch cubes and place in a glass or stainless-steel bowl. Keep chilled until ready to marinate.

Prepare cooked options (shrimp or pulpo)

If using shrimp: cook briefly in boiling salted water until just opaque (about 1–2 minutes), then plunge into ice water, peel/devein if not already, and chop into bite-sized pieces. If using octopus: slice pre-cooked octopus into bite-sized pieces and keep chilled.

Citrus Marinade

In a measuring cup or small bowl combine 3 fl oz fresh lime juice, 1 fl oz fresh lemon juice (optional) and 0.5 fl oz fresh orange juice (optional). Stir to blend. Taste the juice — it should be bright and tangy; adjust lime/lemon ratio as needed.

Pour the citrus mixture over the prepared seafood so it is evenly coated. For raw sashimi-grade fish or ahi, allow to marinate 10–12 minutes (fish will lightly 'cook' but remain tender). For cooked shrimp or pulpo, marinate 5–8 minutes to allow flavors to meld without over-toughening.

Aromatics & Vegetables

While seafood marinates, place 1/2 cup very thinly sliced red onion in cold water for 5 minutes to mellow bite, then drain well. Combine onion, 1/2 cup diced seeded tomato, 1 tsp minced jalapeño (adjust to heat preference), 2 tbsp chopped cilantro, and 1/4 cup diced cucumber (if using) in a mixing bowl.

After the seafood has marinated the appropriate time, drain off about half of the citrus liquid (leave enough to dress the mixture — roughly 1–2 tablespoons). Add the seafood to the vegetable mixture and gently toss to combine.

Seasoning & Finish

Season the combined ceviche with 3/4 teaspoon sea salt and 1/4 teaspoon freshly ground black pepper. Drizzle 1 tablespoon extra-virgin olive oil over the ceviche and gently fold in 1/2 cup diced avocado if using. Taste and adjust salt, heat (add more jalapeño) or citrus if needed.

Cover and chill for 5–10 minutes to allow flavors to marry (serve immediately if you prefer the freshest texture; do not marinate raw fish for more than 20–30 minutes to preserve texture).

Serve chilled in bowls or on tostadas with tortilla chips on the side. Garnish with additional cilantro sprigs and lime wedges if desired.