In large pan, add fish and beer. Poach over medium heat for about 3 minutes. Turn fish over and continue to poach about 2-3 minutes until fish flakes easily with a fork. Remove to a plate and discard liquid.
In a food processor, add fish, potato chips, scallions, egg, vinegar, garlic, mustard, salt and pepper. Pulse until minced and blended.
Using ¼ cup measure, scoop to make 12 cakes. Each cake will be slightly smaller than the full measuring cup. Shape into ½ inch thick patties.
Coat a large nonstick pan with cooking spray. Heat 2 teaspoons of olive oil in pan. Add all patties and cook over medium heat about 2 minutes per side until golden brown.
To make the coleslaw: In a large bowl add all the ingredients and toss well to coat.
To Serve: Place 3 fish cakes on each plate. Serve each with lemon slices and vinegar on the side for dipping. Add about 1 cup Honey Mustard Coleslaw to each plate.
These fish cakes will keep for 2 days. Reheat in a nonstick pan on each side until hot.