Season the red onion with a little olive oil, red wine vinegar, salt, and pepper to taste.
In a small bowl, mix some olive oil, salt, and garlic powder. Use a brush to coat both sides of the vegetables for grilling. Heat a grill pan or grill thoroughly. Grill the vegetables on both sides until marked and cooked. Set aside.

In a large skillet, heat the vegetable oil over medium heat and sauté the garlic and onion.
Add the ground chicken and cook until browned.
Season the browned chicken with paprika, cumin, oregano, pepper, and salt. Cook for 1 minute.

Add the pumpkin or squash, sweet potatoes, carrots, cabbage, bell peppers, tomato sauce, and water. Stir to combine. Cover the skillet and cook over medium heat until the pumpkin and sweet potatoes are tender.
Add the spinach, stir, cover, turn off the heat, and let rest for 5 minutes.

TO SERVE
Arrange the grilled vegetables around the plate.
Spoon the picadillo in the center and top with the marinated onions, chopped eggs, cilantro, and black olives.
Serve immediately.