In a mixing bowl, combine the cornflour, cornmeal, and sea salt. Mix well to ensure the salt is evenly distributed.
Add the warm water and 1 tablespoon of coconut oil to the dry ingredients. Stir until the mixture forms a soft dough. If it feels too dry, add a little more warm water, one tablespoon at a time. Knead the dough gently until smooth, then cover it with a damp cloth to keep it moist while you prepare the filling.
In a separate pan, heat 1 tablespoon of coconut oil over medium heat. Add the chopped plantains and sauté until they are soft and golden brown, about 5-7 minutes. Remove from heat and mash the cooked plantains with a potato masher or fork.
Stir in the coconut sugar and cinnamon into the mashed plantains until well combined. Taste and adjust sweetness if needed.
On a lightly floured surface, divide the rested dough into small balls, about the size of a golf ball. Roll each ball into a thin circle, approximately 5-6 inches in diameter.
Place a generous spoonful of the plantain filling in the center of each dough circle. Fold the dough over to create a half-moon shape. Press the edges together firmly to seal, and use a fork to crimp the edges for an extra secure seal.
In a non-stick frying pan, heat a little coconut oil over medium heat. Carefully place the empanadas in the pan, cooking them for about 3-4 minutes on each side or until golden brown and crispy. Remove from the pan and place on a paper towel to absorb any excess oil.
Serve your Plantain Empanadas warm, perhaps with a side of avocado or your favorite dipping sauce. Enjoy the delightful combination of flavors and textures!