In a medium bowl, place the squeezed potatoes. Add the eggs, onion, and salt and mix well.

In a large frying pan, heat the oil. Form patties with the potato mixture and fry for a few minutes on each side until golden brown.

Let the patties rest on a rack. (This prevents them from getting soggy.)

Prepare avocado mash, adjusting ingredients to your taste.

To assemble, spread some avocado on top of a potato round. Lay some tuna on top. Top with a few radish slices and then a mango slice.