1. To make the arepas: First make the arepa. In a bowl add together the flour, cheese, oil, salt and slowly mix in the water.
2. Use clean hands to mix everything together until a firm dough forms. If it is too dry, add a bit more water.
3. When done, cut into 4 equal pieces and use your hands to form 1 of the pieces into a disc, about 2-3 inches in diameter. Set aside.
4. Heat a large non-stick skillet with a bit of oil to coat the bottom of the pan and add the arepas. Cook on medium heat until the first side is a nice golden brown and then flip over and continue to cook the other side, about 4-5 minutes per side. When done, set aside.
5. To make the black beans: In a small pot, add olive oil and garlic and saute on medium heat for about 2 minutes until the garlic begins to turn golden brown.
6. Add in sazon (or paprika) and stir spices into oil. Then add black beans, liquid included and salt and pepper and cook on medium heat until it comes to a gentle bowl.
7. Use the back of a spatula to gently press down on some of the beans to make for a thicker consistency. Cook for about 15 minutes until tender. Taste for seasoning.
8. To make the plantains: Add ripe plantains to a lightly oiled skillet and fry on the first side until golden brown, for about 3-4 minutes. Then flip over and cook on second side until golden brown. The plantain should soften and get sweeter as the sugars are cooked out. When done, set aside on a paper towel lined plate.
9. To make the avocado sauce: Add all ingredients to a food processor and blend together. Add a bit of water, to thin out consistency if desired.Taste for seasoning.
10. To assemble: Cut one of the arepas in half, opening up like a sandwich, but don't cut all the way through. It should be like a pocket. Then spoon in 1-2 Tb of black beans, more shredded Havarti cheese, plantains and avocado sauce.