Place the chicken wings in an 8-quart slow cooker.
In a mixing bowl, whisk together the ketchup, honey, adobo sauce, apple cider vinegar, salt, black pepper, onion powder, and garlic powder until smooth.
Reserve half of the sauce for finishing the wings. Pour the remaining sauce over the chicken wings and toss until evenly coated.
Cover and cook on High for 4 hours, or until the wings are tender.
Line a baking sheet with aluminum foil and lightly coat it with cooking spray. Transfer the cooked wings to the prepared baking sheet.
Brush the reserved sauce over the wings.
Place the wings under the broiler for 3 to 4 minutes, or until the sauce begins to caramelize and the edges are lightly browned. Watch closely to prevent burning.
Transfer to a serving platter and garnish with chopped parsley if desired.
Christina's Notes
Pat the wings dry before adding them to the slow cooker. This helps the sauce cling better to the chicken.
Keep an eye on the wings during the final broil. The honey in the sauce can brown quickly.
If you'd like a thicker sauce, whisk together 1 teaspoon cornstarch and 1 teaspoon water. Simmer the reserved sauce for a few minutes until slightly thickened before brushing it on the wings.
Store leftovers in an airtight container in the refrigerator for up to 4 days.
Reheat in a 375 degree F oven until warmed through. Avoid microwaving if possible to maintain the best texture.