Combine cornstarch and pepper in re-sealable food storage bag.
Add chicken.
Shake to coat with cornstarch mixture.
In a large skillet, over medium-high heat, heat oil.
Brown chicken about 2 minutes on each side.
Place chicken in a crock pot.
In a small bowl, combine soy sauce, vinegar, ketchup, sweet chili sauce, brown sugar, garlic, ginger, pepper flakes, and cashews; pour over chicken.
If you like the cashews to be softer, add them during the cooking process; if you want more of a crunch, add them right before serving.
Cook on low for 3 to 4 hours.
Serve over rice.
