Preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper or lightly grease it.
Prepare the broccoli, Brussels sprouts, sweet potato, and chickpeas. Pat the chickpeas completely dry.
Combine the vegetables and chickpeas in a large bowl with olive oil, garlic powder, salt, and black pepper. Toss until evenly coated.
Spread everything into a single layer on the prepared baking sheet.
Roast for 15 minutes.
Stir the vegetables and chickpeas, then continue roasting for another 5 minutes until tender and golden.
For extra crispy chickpeas, broil for 2 minutes, watching carefully.
While everything roasts, whisk together Dijon mustard and tahini. Gradually whisk in water until smooth. Add apple cider vinegar, date syrup, lemon juice, salt, pepper, and red pepper flakes.
Transfer the roasted vegetables to a serving bowl and drizzle generously with the dressing.
Serve the 30 Minute Roasted Chickpeas and Veggies immediately while warm.