Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Cut the chicken breast into 1-inch cubes and chop the red bell pepper into bite-sized pieces.
Rinse and drain the chickpeas, then pat them completely dry with a paper towel to ensure they get crispy.
In a large bowl, toss the chicken, chickpeas, broccoli, and peppers with olive oil, garlic powder, smoked paprika, sea salt, and black pepper until evenly coated.
Spread the mixture in a single layer on the prepared baking sheet.
Roast for 20-25 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, and lemon juice in a small bowl until smooth.
Transfer the roasted chicken and veggie mixture to a serving bowl and drizzle with the creamy tahini sauce before serving.