Peel and chop the plantain into chunks about 1 ½” thick. Heat the vegetable oil in a large pan and fry the plantains, turning occasionally until they are golden and soft. Transfer the plantains into a bowl and add the butter, salt, and pepper. Mash them until a somewhat even consistency is achieved. Leaving some larger chunks is ok.
Using your hands, take the plantain dough and form balls. Using your fingers, make a hole in the middle of each ball and fill it with your Queso Ecuatoriano. Once filled, re-form the small balls. Heat up more vegetable oil and fry the balls turning them over very gently in order to fry all sides. Fry until they are a crispy golden brown and serve hot.
If you are having trouble keeping them from breaking apart, we recommend using a deep soup pot filled ½ way with vegetable oil. Fry the balls one at a time using a perforated frying spoon.