Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Dice the chicken breast into one-inch cubes and chop the broccoli and red bell pepper into bite-sized pieces.
Rinse and drain the chickpeas, then pat them thoroughly dry with a paper towel to ensure they get crispy in the oven.
Place the chicken, chickpeas, broccoli, and bell pepper onto the prepared baking sheet in a single layer.
Drizzle the olive oil over the ingredients and sprinkle evenly with the sea salt, black pepper, garlic powder, and smoked paprika.
Toss everything together with your hands or tongs until the chicken and vegetables are well-coated in the oil and spices.
Roast in the center of the oven for 20 to 25 minutes, or until the chicken is cooked through and the vegetables have slightly charred, caramelized edges.
While the bowl ingredients roast, whisk together the tahini and lemon juice in a small bowl, adding a teaspoon of water at a time until it reaches a smooth, pourable consistency.
Transfer the roasted chicken and vegetable mixture to a serving bowl and drizzle the zesty tahini dressing over the top before enjoying warm.