Bring a large pot of water to a boil. Add the chicken wings and boil for 15 minutes to remove much of the fat. Remove the wings and place in a large mixing bowl. Meanwhile, in a saucepan, combine the vinegar, sugar, pineapple juice, Ac’cent, ketchup, sesame oil, garlic powder and beer and bring to a boil, stirring frequently. Allow to boil for 4 minutes. Turn down the heat to low.
With a ladle, remove 1/2 cup of the sauce and combine with the cornstarch in a separate small bowl. Whisk together to create a slurry and then whisk back into the saucepan. Heat for another 3 minutes until thickened and then remove from the heat. Allow to cool slightly and thicken.
Pour half of the sauce over the wings and toss. Preheat the broiler and place the sauced wings on a sheet pan about 2 inches from the broiler. Broil for 8 minutes and then with tongs, flip over and broil for another 8 minutes, until golden brown.
Baste again with remaining sauce before serving and sprinkle with sesame seeds. You can use any of the leftover sauce for dipping.