01 - 
                Coat a 5–6‑quart slow cooker with nonstick cooking spray.
              
              
              
                02 - 
                Combine brown sugar, ketchup, chicken broth, onion soup mix, salt, pepper and red pepper flakes in a mixing bowl.
              
              
              
                03 - 
                Heat oil in a nonstick skillet over medium‑high, season chicken with salt and pepper, sauté 3 minutes per side until golden.
              
              
              
                04 - 
                Transfer seared chicken and sauce mixture to slow cooker, cook on low for 7–8 hours until chicken reaches 165°F.
              
              
              
                05 - 
                Pour sauce into a small saucepan, whisk in cornstarch slurry and simmer until it bubbles and thickens to a glaze.
              
              
              
                06 - 
                Plate chicken over mashed potatoes or rice and spoon glaze over top before serving.