Ingredients:

  • Canned tuna, drained — about 12 oz (340 g) total drained weight (approx. 2–3 standard 5 oz / 142 g cans); solid white (albacore) or light tuna packed in water, drained
  • Fresh lime juice — from 3 limes (about 6 tablespoons / 90 ml)
  • Red onion, very thinly sliced — 1 small (about 4 oz / 110 g)
  • Jalapeño, finely chopped (seeds removed for milder) — 1 small (about 15–20 g)
  • Tomato, seeded and diced — 1 medium (about 1 cup / 160 g)
  • Seeded cucumber, diced — 1 small (about 1 cup / 150 g) (optional)
  • Fresh cilantro, chopped — 2 tablespoons (about 8 g)
  • Extra-virgin olive oil — 1 tablespoon (15 ml)
  • Ground cumin (optional) — 1/2 teaspoon
  • Kosher salt — start with 1/2 teaspoon (3 g), adjust to taste
  • Freshly ground black pepper — to taste
  • Ripe avocado, diced — 1 medium (about 1 cup / 150 g) (fold in just before serving)
  • Lime wedges — for serving
  • Tortilla chips, tostadas, or butter lettuce leaves — for serving
  • Optional add-ins (use one or two if desired): canned sweet corn, drained — 1/2 cup (80 g); cooked black beans, rinsed and drained — 1/2 cup (120 g); chopped radish — 2–3 radishes thinly sliced

Instructions:

  1. Drain canned tuna very well in a fine-mesh strainer; press gently to remove excess liquid, then flake tuna into bite-size pieces with a fork without over-mashing.
  2. Thinly slice red onion (optional: soak slices in cold water for 5 minutes to soften), seed and finely chop jalapeño, seed and dice tomato and cucumber, and chop cilantro; dice avocado last.
  3. In a medium bowl, whisk together fresh lime juice, extra-virgin olive oil, ground cumin (if using), kosher salt and freshly ground black pepper.
  4. Add flaked tuna, sliced onion, chopped jalapeño, diced tomato, cucumber, and chopped cilantro to the bowl and toss gently to coat; cover and chill for 20–30 minutes to let flavors meld.
  5. Just before serving, gently fold in diced avocado, taste and adjust seasoning with more salt or lime as needed, and serve chilled with tortilla chips, on tostadas, or in lettuce cups with lime wedges.