Mix together the seasoning blend. Pat the turkey wings dry, then season them generously on all sides.
Add the sliced green bell pepper and onion to the bottom of the crockpot. Pour in the chicken broth, add the thyme, and sprinkle any remaining seasoning over the vegetables.
Arrange the turkey wings on top of the vegetables so most of the seasoned surface stays above the broth.
Cover and cook on HIGH for about 4 hours. Begin checking at that point. The meat should be fork-tender and pull easily away from the bone while the wings still hold together.
Remove the cooked turkey wings from the crockpot.
Whisk together the cornstarch and cold water until smooth. Stir the slurry into the hot liquid and vegetables in the crockpot until the gravy thickens.
Serve the turkey wings with the peppers, onions, and gravy spooned over the top.