Wash and pat dry chicken thighs. Place in a large bowl. Prepare the basting mixture by placing the egg and vegetable oil in a medium bowl and whisk vigorously to combine. Add the vinegar, salt, poultry seasoning, and pepper, whisking to combine. Set aside. Heat a grill plate to medium high heat. Brush with olive oil. Arrange the thighs on the grill. Immediately start basting the chicken with the basting mixture. Baste often, about once every 3 to 5 minutes, stirring the basting mixture as you use it. Continue grilling until the chicken turns a rich golden brown and the meat is cooked through, 15 to 20 minutes per side and internal temperature is 165 degrees. Serve with BBQ Sauce. Serves 4