Open the canned tuna and thoroughly drain the liquid. Transfer tuna to a medium mixing bowl and use a fork to break it into flakes, leaving some slightly chunkier pieces for texture.

Prepare Vegetables

Finely dice the celery and red onion. Halve the cherry tomatoes. Chop the parsley. Add celery, red onion, cherry tomatoes, and chopped parsley to the bowl with the flaked tuna.

Add Avocado

Peel and pit the avocado, then dice it into roughly 1/2-inch pieces. Gently fold the avocado into the tuna mixture to avoid mashing it — combine until evenly distributed.

Assemble on Greens (optional)

If using salad greens, divide them among serving plates or a large platter and spoon the tuna-avocado mixture on top. Alternatively, serve the tuna mixture as a sandwich filling or with crackers.

Dressing

In a small bowl or jar, whisk together mayonnaise, Greek yogurt, lemon juice, Dijon mustard, and olive oil until smooth and emulsified.

Season the dressing with sea salt, freshly ground black pepper, and optional hot sauce or a pinch of cayenne for heat. Taste and adjust acidity or seasoning by adding more lemon juice or salt if needed.

Pour the dressing over the tuna, avocado, and vegetable mixture. Gently fold everything together until evenly coated, taking care not to overwork the avocado.

Chill (optional) for 10–15 minutes to let flavors meld, or serve immediately. Garnish with a sprinkle of extra chopped parsley or a grind of black pepper.