Combine pork strips, cumin, and garlic pepper blend in a large resealable plastic bag. Shake until pork is coated.

Heat vegetable oil in a large skillet over medium heat. Add pork; cook and stir until browned, 4 to 5 minutes. Add onion, red bell pepper, and green bell pepper; cook until fragrant, about 2 minutes. Stir in barbeque sauce; simmer until flavors combine, about 2 minutes.

Serve pork mixture over flour tortillas.