Cut flank steak into thin strips. In a ziplock bag add flank steak strips & cornstarch. Shake to coat.
Add olive oil, minced garlic, soy sauce, water, brown sugar and carrots to slow cooker. Stir ingredients. Add coated flank steak & stir again until coated in the sauce.
Cook for high 2-3 hours or on low 4-5 hours until cooked throughout and tender. Can serve over rice and garnish with green onions.