Recipe: Causa de atún (tuna causa)

Boil potatoes until tender. While potatoes cook, chop onion finely and soak in cold water.Drain potatoes, mash until smooth and let cool down.Mix mash with lime juice, olive oil and ají amarillo paste. Season with salt.Drain onion and tuna, mix both with mayonnaise and season with salt.If you have a plating ring, use it for making individual portions. Otherwise, use a smallish baking dish and then cut into portions. Spread 1/2 of the mash, top with avocado slices (leave a few for garnish) and tuna mix.Spread rest of the mash on top of the filling.Serve on lettuce leaves. Garnish with egg and avocado slices, olives and parsley.