I love plantains! Of course, the sweeter you want the plantain, the riper you have to let it get. You want to let that peel get pretty dark before cooking.
Once it's ripe, I peel it and cut it into circular chunks (not too thin, not too thick). Then I fill a ziploc bag full of a marinade that I make out of lemon juice, cumin, coriander, and chili powder, put the plantain slices in there, give it a shake, let it sit for a few minutes. A bowl works too, but I love using ziploc bags to make sure it's well coated.
After that, I heat some canola oil in a pan, place the plantains in there and let them fry on low heat for about a minute or two, until the outside turns dark brown. Flip each slice and do the same. The cumin and coriander give it that island-y flavor, the chili powder adds a kick of spice, and it's nice and crispy on the outside but as soon as you bite in, you get all of that sweetness. So good.