Ensalada de patatas con atún is a traditional salad originating from Spain. The salad is usually made with a combination of potatoes, canned tuna, lemon juice, white wine vinegar, lettuce leaves, hard-boiled eggs, olives, olive oil, and salt.
The tuna is flaked into a bowl and sprinkled with lemon juice. The potatoes are cooked, drained, peeled, and sliced. A mixture of vinegar, salt, and olive oil is poured over the potatoes. They're mixed with the tuna and placed on a bed of lettuce in a salad bowl.