1 (2-inch) piece fresh ginger, peeled and chopped
4 garlic cloves, peeled and chopped
¾ cup packed dark brown sugar
¼ cup plus 1 tablespoon soy sauce
1 teaspoon Sriracha sauce, divided
¼ teaspoon cayenne pepper, divided
4 pounds chicken wings, halved at joint and wingtips removed
¼ cup water
¼ cup tomato paste
sesame seeds, optional
Place ginger, garlic, ¼ cup dark brown sugar, 1 tablespoon soy sauce, ½ teaspoon Sriracha sauce, and ⅛ teaspoon cayenne pepper in a food processor and pulse until a paste is formed.
Place chicken wings and paste in crock pot and toss to coat.
Cover and cook on LOW for 3 to 4 hours. Use slotted spoon to remove wings and place them in a large bowl lined with paper towels. Discard liquid in crock pot.
Let wings cool 20 minutes or you can refrigerate them up to 24 hours.
Place oven rack in lower-middle of oven. It should be 10 to 12 inches from the heating element. Turn oven to BROIL.
Set a wire rack inside a rimmed baking sheet and spray rack with cooking spray.
In a medium bowl, whisk together water, tomato paste, remaining ½ cup dark brown sugar, ¼ cup soy sauce, ½ teaspoon Sriracha sauce, and ⅛ teaspoon cayenne pepper.
Pour half of sauce in bowl with chicken wings and gently toss to coat. Place wings skin side up on prepared rack.
Broil until wings are lightly charred, about 10 to 15 minutes. Flip wings over and brush with sauce. Broil 3 minutes. Flip and brush with sauce one more time and broil 2 minutes.
Sprinkle with sesame seeds.
Broiling times are estimates. The chicken will already be cooked through so you are just broiling long enough to get a good, charred coating of sauce on the wings. Watch them carefully. If they are not charring, you may need to move the rack closer to the heating element.
It helps to drain chicken wings on a layer of paper towels when you remove them form the crock pot. They will caramelize better if excess liquid is removed.