Gather all ingredients.

Whisk soy sauce, brown sugar, sherry, mustard, and garlic powder together in a bowl until combined.

Arrange chicken wings in a 9x13-inch baking dish; pour marinade over chicken and cover with plastic wrap. Marinate in the refrigerator for at least 2 hours.

Preheat the oven to 375 degrees F (190 degrees C). Remove plastic wrap from the baking dish.

Bake in the preheated oven, basting occasionally, until chicken wings are no longer pink in the center, about 1 hour. An instant-read thermometer inserted into the center should read at least 165 degrees F (74 degrees C).