Found this on Pinterest and it looked super easy and the blogger said they're crazy good.
1 3" piece fresh ginger, peeled and chopped
4 garlic cloves, peeled
3/4 cup packed dark brown sugar
1/4 cup soy sauce
1/2 tsp cayenne pepper
4 lbs chicken wings, halved at joint and tips removed
1/4 cup water
1/4 cup tomato paste
Pulse ginger, garlic, 1/4 cup brown sugar, 1 Tbsp soy sauce and 1/4 tsp cayenne pepper in food processor until finely ground. Add mixture to slow-cooker insert. Add chicken and toss to coat.
Cook and Cool
Cover and cook on low until fat is rendered and chicken is tender, about 3-4 hours. Using slotted spoon, remove wings from slow-cooker and transfer to clean large bowl (discard liquid in slow-cooker). Let wings cool about 20 min (or cool briefly and refrigerate up to 24 hours).
Sauce and Broil
Adjust oven rack to lower-middle position and heat broiler. Set wire rack inside rimmed backing sheet and spray rack with non-stick cooking spray. Whisk water, tomato paste, remaining sugar, remaining oy sauce, and remaining cayenne pepper in a bowl. Add half the sauce to a bowl with cooled wings and toss gently to coat. Arrange wings, skin side up, on prepared rack. Broil until wings are lightly charred and crisp around the edges, about 10-15 minutes. Flip wings, brush with remaining sauce, and continue to broil until well caramelized, about 3 minutes. Serve.
Note: In step 3, rack should be 10" to 12" from heating element. Don't wander off while the wings are in the oven.