Toss together the veggies and garlic in a large bowl. Drizzle with olive oil and toss to coat. Sprinkle with about ¾ of the spice mixture and toss again to coat.
Place the shrimp in the same large bowl. Drizzle olive oil over shrimp and toss to coat. Sprinkle the remaining ¼ of fajita spice mixture over shrimp and toss again to coat.