Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper for easy cleanup.
Pat the chicken breast completely dry with paper towels to ensure a good sear, then cut into uniform 1-inch cubes.
Rinse the canned chickpeas under cold water and drain thoroughly, then pat them very dry with a clean kitchen towel so they become crispy in the oven.
Place the chicken, chickpeas, and broccoli florets on the prepared baking sheet, then drizzle with olive oil and sprinkle with sea salt, black pepper, and dried oregano.
Toss everything together until evenly coated, then spread into a single layer to ensure even roasting across the pan.
Roast in the oven for 18 to 22 minutes, or until the chicken is cooked through and the chickpeas have reached a satisfying crunch.
While the bowl components roast, whisk together the plain Greek yogurt, lemon juice, and minced garlic in a small bowl until smooth.
Transfer the roasted chicken and vegetables to a serving bowl and finish by drizzling the zesty lemon-garlic sauce over the top.