Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Dice the chicken breast, bell pepper, zucchini, and red onion into uniform bite-sized pieces to ensure even cooking.
Drain and rinse the chickpeas, then pat them thoroughly dry with a clean kitchen towel to help them crisp up in the oven.
Place the chicken, chopped vegetables, and dried chickpeas onto the prepared baking sheet.
Drizzle the mixture with olive oil and sprinkle with garlic powder, dried oregano, sea salt, and black pepper.
Toss everything together with your hands or tongs until well-coated, then spread into a single layer.
Roast for 20-25 minutes, tossing halfway through, until the chicken is cooked through and the vegetables are tender and slightly caramelized.
Remove from the oven and immediately drizzle with fresh lemon juice before serving warm in a bowl.