Preheat your oven to 400°F and line a large sheet pan with parchment paper for easy cleanup.
In a large bowl, toss the shrimp, chickpeas, broccoli florets, and diced bell pepper with olive oil, sea salt, black pepper, and garlic powder until evenly coated.
Spread the mixture in a single layer on the prepared baking sheet, ensuring the ingredients aren't overcrowded so they roast properly.
Roast for 12 to 15 minutes until the shrimp are pink and opaque and the broccoli edges are slightly charred and tender.
While the bowl components roast, whisk together the Greek yogurt, lemon juice, and tahini in a small ramekin until the sauce is smooth and creamy.
Transfer the roasted shrimp and vegetables to a serving bowl, drizzle with the lemon-tahini sauce, and garnish with fresh parsley.