Preheat your oven to 375°F and lightly grease a small oven-safe baking dish.
Peel the ripe plantain and slice it lengthwise into four or five thin strips.
Heat a non-stick skillet over medium heat with half of the olive oil and sear the plantain strips until golden brown and tender on both sides.
Remove the plantains and add the remaining olive oil to the skillet, then sauté the diced onion, bell pepper, and garlic until softened.
Add the ground beef to the skillet along with the sea salt, black pepper, dried oregano, and ground cumin, cooking until the meat is fully browned.
Stir in the tomato paste and a tablespoon of water, simmering for two minutes until the mixture is well combined and fragrant.
Lay half of the seared plantain strips in the bottom of the prepared baking dish to create a base layer.
Spread the beef mixture evenly over the plantains, then top with the remaining plantain strips.
Pour the egg whites over the entire casserole, ensuring they seep into the layers to act as a binder.
Bake for 20 minutes until the egg is set and the edges are slightly crisp and bubbly.