Peel the plantains and cut them into 1 inch (1½ cm) slices.
Heat oil in a deep pan and deep fry the patties until they are a slightly brown colour.
Remove the patties from the pan.
Place a plantain slice into the carved-out circle of the tostonera (or whatever you are using instead) and squash it to make a flat, round patty. Proceed like this with all fried patties.
Return the patties to the pan with the hot oil and fry them a second time, until of golden brown color.
Drain on a kitchen towel, sprinkle with salt (generously if health permits, it really does make a difference!) while they are still warm.
Eat them while warm. You can keep them warm in an oven for a while. They’ll lose some of their crispness, but are still good!