Heat oven to 350°F. Heat 1 tsp. oil in large skillet over medium-high heat. Add onions and peppers; cook until soft, about 5 minutes. Stir in recaito, sazón and garlic; cook until garlic is fragrant, about 1 minute more. Add meat to vegetable mixture. Cook, breaking up meat into small pieces with wooden spoon, until meat is browned. Stir in tomato sauce and olives; season with adobo. Continue to cook until flavor comes together and meat and vegetables are evenly combined. Transfer meat mixture to bowl to cool.
Meanwhile, in bowl of food processor, puree ripe plantains until smooth, about 1 minute; set aside. Grease 3-qt. casserole dish with remaining olive oil.
To assemble casserole, using spatula, evenly spread half pureed plantain mixture on bottom of prepared dish. Spread cooled meat mixture evenly over plantain layer. Top with remaining plantains, smoothing mixture evenly over meat. Sprinkle with cheese. Bake until casserole is cooked through and cheese is melted and golden brown, about 30 minutes. Serve with salad, if desired.