Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Pat the chickpeas completely dry with a paper towel to ensure they achieve a crispy texture during roasting.
Place the cubed chicken breast, chickpeas, broccoli florets, and chopped red bell pepper onto the prepared baking sheet.
Drizzle the olive oil over the ingredients and sprinkle evenly with sea salt, black pepper, garlic powder, and smoked paprika.
Toss everything together until well-coated, then spread into a single, even layer to ensure uniform cooking.
Roast for 20 to 25 minutes, tossing halfway through, until the chicken is cooked through and the chickpeas are golden and crisp.
While the bowl base roasts, whisk the tahini and lemon juice in a small bowl, adding a teaspoon of water at a time until it reaches a pourable consistency.
Transfer the roasted chicken and vegetables to a serving bowl and finish by drizzling the lemon-tahini dressing over the top.