Boil plantains for 15 minutes or until skin starts to peel off. Remove skin and transfer to a bowl. Mash plantains until pureed and add salt to taste. Once cool, form small balls with the dough and press them round with the palm of your hand. Add beans and cheese to your liking. Proceed to seal edges with a fork. Heat oil in pan and fry empanadas on both sides until brown. Enjoy!