Add 1/2 cup of vegetable oil into a medium size cast iron pan. Turn the heat to medium while you slice up the plantain.
Cut off the ends of the plantains. Using a sharp knife, slice the peel lengthwise, being careful not to slice the plantain. Then, slice the plantain into 1 inch pieces. I like to slice them on a bias cut, but you don't have to.
Add half of the sliced plantains to the pan on the stove. Make sure they are not stacked on top of each other as they will not cook evenly this way. Let them cook for about 1 minute. You will see the sides of them begin to turn brown. At this point, you will want to flip them over.
Once you have flipped them over, let them cook for about another minute, or until they start to brown. You want to be careful not to overcook them.
The plantains cook quickly, so keep a careful watch over them. Once they are done, remove them with a slotted spoon and put them onto a paper towel-lined plate to drain the oil. Salt them as soon as they come out of the pan as this helps the salt stick to the fritters.