Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Pat the chicken breast and chickpeas very dry with paper towels to ensure they get crispy during roasting.
Cut the chicken into 1-inch bite-sized cubes and place them on the baking sheet along with the chickpeas, broccoli florets, and sliced bell peppers.
Drizzle the olive oil over the mixture and sprinkle evenly with sea salt, black pepper, garlic powder, and smoked paprika.
Toss everything together with your hands or a spatula until the ingredients are well-coated, then spread them out into a single layer.
Roast in the oven for 20-25 minutes, tossing the ingredients halfway through, until the chicken is cooked through and the chickpeas are golden and crisp.
While the bowl base roasts, whisk together the tahini and lemon juice in a small bowl, adding a teaspoon of warm water at a time until it reaches a pourable consistency.
Transfer the roasted chicken, chickpeas, and vegetables to a serving bowl and finish by drizzling the creamy tahini dressing over the top.