1. Heat 1 tablespoon oil in a large skillet over medium-high heat; add onion, bell pepper, and salt, and cook 3 minutes. Add garlic, cumin, and chili powder, and cook 1 minute or until vegetables are crisp-tender. Remove from heat, and stir in 2 tablespoons lime juice and 2 tablespoons cilantro.
2. Heat tortillas according to package directions.
3. Whisk together remaining 1 tablespoon oil, 4 tablespoons lime juice, and 2 tablespoons cilantro in a small bowl; season with salt. Drizzle dressing over chicken; toss to coat. Arrange chicken, vegetables, and warm tortillas on platter. Serve with toppings.