In a large skillet over medium-high heat, add oil and saute peppers, celery, onion and cumin until lightly brown, about 10 to 15 minutes. Add tomatoes, oregano and garlic. Continue to saute until tomatoes blister and break open, about 5 to 10 minutes. Transfer contents to a blender and puree until desired consistency.
Pull apart breast meat from chicken and divide among tortillas. Top with beans, cabbage and sauce. Roll up and enjoy.