In a bowl, whisk together ¼ cup cornstarch, 2 Tbsp sesame oil, ½ tsp garlic powder, ½ cup soy sauce, ¾ cup brown sugar, 1 diced onion, and ¼ tsp red pepper flakes until combined.
Place 1.5 lbs flank steak in a crock pot and pour the sauce mixture over the meat.
Cover and cook on low for 6–8 hours or high for 3–4 hours.
Remove the meat, cut into pieces or shred, then return it to the crock pot and stir to coat.
Serve over rice.
Video
Notes
We love serving this topped with sliced green onions and sesame seeds. Refrigerate the leftovers in an air tight container for up to 5-7 days.