Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Pat the chicken breast dry with a paper towel and cut it into 1-inch cubes.
Drain and rinse the chickpeas, then pat them thoroughly dry to ensure they become crispy during roasting.
Dice the red bell pepper and zucchini into bite-sized pieces.
On the prepared baking sheet, combine the chicken, chickpeas, bell pepper, and zucchini.
Drizzle with olive oil and sprinkle with sea salt, black pepper, garlic powder, and smoked paprika; toss until everything is evenly coated.
Roast in the oven for 20-25 minutes, tossing halfway through, until the chicken is cooked through and the chickpeas are golden and crisp.
While the mixture roasts, whisk together the Greek yogurt, lemon juice, and tahini in a small bowl until smooth.
Place the baby spinach in a serving bowl and top with the warm roasted chicken and vegetable mixture.
Drizzle the zesty lemon-tahini yogurt sauce over the top and serve immediately.