For the spice blend, mix all spices, salt and pepper together in a small bowl.
Wash and prepare vegetables as directed. Place vegetables in a very large mixing bowl or on a sheet pan and drizzle with olive oil. Toss gently to coat with oil.
Sprinkle spice mix over vegetables and gently toss and rub spice mix into vegetables. Let coated vegetables sit for 10 minutes.
Preheat a grill to medium-high heat.
Working in batches as necessary, grill vegetables until tender and lightly charred on each side, about 8-10 minutes per batch.
Let vegetables cool slightly, and then slice into serving pieces.
For yogurt sauce, mix together Greek yogurt, lime juice, zest and scallions. Season with a pinch of salt if desired.
Serve with yogurt sauce, and brown basmati rice if desired.
Notes
Store any leftover vegetables and yogurt sauce in the refrigerator for 3-4 days.
Recipe adapted slightly from Food & Wine