For The Marinade:
1 cup (8fl oz/250 ml) cider vinegar
2 tablespoons vegetable oil
2 tablespoons Worcestershire sauce
2 tablespoons chili powder
1 teaspoon red pepper flakes
1 teaspoon salt
1 teaspoon freshly ground pepper
1 tablespoon Tabasco (hot red pepper)sauce
4 lb chicken wings (about 24)

For The Blue Cheese sauce:
2/3 cup (5fl oz/160 ml) sour cream
1/2 cup (4fl oz/124 ml) mayonnaise
1 large clove garlic, minced
2 teaspoons Worcestershire sauce
1 cup (4fl oz/125 g) crumbled blue cheese
salt
freshly ground pepper
2 tablespoons, more or less, milk
celery sticks

To make the marinade:
In a small bowl stir together the vinegar, oil, Worcestershire sauce, chili powder, red pepper flakes, salt, pepper and Tabasco sauce. Place the chicken wings in a large plastic food storage bag and pour in the marinade. Press out the air and seal the bag tightly. Massage the bag gently, to distribute the marinade. Set in a large bowl and refrigerate for several hours, turning and massaging the bag occasionally.

To make the blue cheese sauce:
In a small bowl whisk together the sour cream, mayonnaise, garlic, Worcestershire sauce and blue cheese. Season to taste with salt and pepper. Add enough milk to make a sauce with the consistency of pancake batter.
Cover and refrigerate.

Prepare a fire in the grill. Remove the wings from the marinade and pat them dry with absorbent paper towels; reserve the marinade. Arrange the wings on the grid. Grill, turning frequently and brushing with the reserved marinade, until cooked through, 25-30 minutes.

Serve with the dipping sauce and celery sticks.