Preheat a cast iron skillet over medium heat with about 1-1½ inches of vegetable or canola oil (about 350°)
Peel the plantains by taking a knife and making a slit from the top to the bottom of a plantain. Pull the skin away from the flesh with your fingers, using a knife to cut any tough parts if necessary.
Slice the peeled plantains into one-inch chunks
Place the chunks flat side down in the oil and fry for 2-3 minutes until they develop a light gold color. Flip to the other flat side and repeat.
Remove the plantains from the oil and drain on a paper towel.
Immediately smash plantains by placing them flat side down on the counter and pressing down with a small sauce pan, or use a wooden tostone press Place flattened plantains back into the hot oil and fry for another 2-3 minutes
Remove from oil and place on a paper towel to drain. Salt immediately and serve
