Combine steak, chili powder, cumin, and 1/4 teaspoon salt; toss well. Set aside.
Combine tomato, olives, green onion, cilantro, 2 tablespoons lime juice, and remaining 1/4 teaspoon salt; set aside.
Heat a large nonstick skillet over medium- high heat until hot. Coat beef mixture lightly with cooking spray; toss well. Add beef mixture to skillet; cook, stirring constantly, 3 minutes or until browned. Remove beef mixture from skillet. Set aside; keep warm.
Pat pepper stir-fry dry with paper towels; add to skillet. Cook over high heat 4 minutes or until lightly browned. Return beef mixture to skillet. Add remaining 1 tablespoon lime juice; stir well. Serve with tortillas, reserved cilantro and olive salsa, and sour cream.