Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Chop the zucchini, eggplant, and red bell pepper into uniform 1-inch cubes to ensure even roasting.
Slice the chicken breast into bite-sized pieces and place them in a large mixing bowl with the chopped vegetables.
Add the olive oil, minced garlic, dried oregano, sea salt, and black pepper to the bowl, tossing thoroughly to coat every piece.
Spread the chicken and vegetable mixture in a single layer across the prepared baking sheet.
Roast in the oven for 20 minutes until the chicken is cooked through and the vegetables are tender and slightly caramelized.
Remove the tray from the oven, pour the tomato puree over the mixture, and stir gently to combine.
Return the tray to the oven for an additional 5 minutes to allow the sauce to warm through and thicken.
Garnish the dish with freshly torn basil leaves before serving warm.