Preheat oven to 450°F. Combine all fajita seasoning ingredients. Set aside.
Slice peppers and onions into long, thin slices.
Place peppers, onions, and shrimp on baking sheet. Drizzle with olive oil, and season with fajita seasoning. Toss to coat.
Broil on center rack for 8 minutes. Toss with tong. Move oven rack to top and add sheet pan back to oven for an additional 2 minutes to add char.
Squeeze lime juice over fajita filling before serving. Serve with warm tortillas, cilantro, lime wedges, and sour cream.