Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Pat the chicken breast dry with paper towels and cut into 1-inch bite-sized cubes.
Drain and rinse the chickpeas, then pat them thoroughly dry to ensure they get crispy in the oven.
Place the chicken, chickpeas, chopped zucchini, and chopped bell pepper onto the prepared baking sheet.
Drizzle with olive oil and sprinkle with sea salt, black pepper, smoked paprika, and garlic powder.
Toss everything together with your hands or a spatula until the ingredients are evenly coated in oil and spices.
Spread the mixture into a single layer and roast for 20-22 minutes, tossing halfway through, until the chicken is cooked through and the chickpeas are golden.
While the bowl base roasts, whisk together the Greek yogurt, tahini, lemon juice, and water in a small bowl until the sauce is smooth and pourable.
Transfer the roasted chicken and veggie mixture to a serving bowl and drizzle generously with the creamy tahini sauce.