Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Dice the eggplant, zucchini, and red bell pepper into uniform 1-inch cubes to ensure even roasting.
Toss the vegetables on the baking sheet with 0.5 tablespoons of olive oil, sea salt, and black pepper.
Roast the vegetables for 20-25 minutes until they are tender and slightly caramelized at the edges.
While the vegetables roast, cut the chicken breast into bite-sized pieces and season with dried thyme and oregano.
Heat the remaining 0.5 tablespoons of olive oil in a large skillet over medium-high heat.
Add the chicken to the skillet and sear for 5-7 minutes until golden brown and cooked through.
Reduce the heat to medium and stir in the minced garlic, cooking for 1 minute until fragrant.
Add the roasted vegetables and tomato puree to the skillet, stirring gently to combine.
Let the ratatouille simmer for 5 minutes to allow the flavors to meld, then serve garnished with torn fresh basil.