Preparation

• Combine onion, honey, brown sugar, soy sauce, butter, mustard powder, and garlic together in a saucepan over medium heat; cook until hot, about 5 minutes.
• Arrange wings in an even layer in a shallow baking dish; pour sauce over wings and toss to coat. Cover dish with plastic wrap and marinate in the refrigerator for 1 hour to overnight.
• Preheat the oven to 350 degrees F (175 degrees C).
• Bake in the preheated oven until wings no longer pink at the bone and juices run clear, turning occasionally, about 90 minutes. An instant-read thermometer inserted near the bone should read 165 degrees F (74 degrees C).