Preheat your oven to 375°F (190°C).
In a skillet, heat some oil over medium heat and sauté the onions and garlic until soft.
Add the ground beef to the skillet, cooking until browned.
Stir in the red bell pepper, corn, black olives, cumin, paprika, salt, and pepper.
Once the mixture is heated through, remove from heat and set aside.
Prepare the mashed potatoes by boiling and mashing the potatoes until smooth.
Spoon the meat mixture into a greased baking dish.
Spread the mashed potatoes over the filling evenly.
If using, sprinkle cheese on top of the mashed potatoes.
Bake in the preheated oven for about 25-30 minutes, or until the top is golden and bubbling.
Let it cool for a few minutes before serving.