Mix pork, breadcrumbs, egg, garlic, and herbs in a bowl and season well.
Divide the mixture into 12 pieces and shape into sausages.
Fry sausages in 2 tablespoons of oil over low to medium heat for 12-15 minutes until golden.
Boil potatoes in salted water for 10 minutes then reduce water and simmer until tender.
Drain, peel, and mash potatoes with 50g of butter.
Sauté cabbage with remaining 50g of butter and 2 tablespoons of water for 5-7 minutes.
Combine cabbage, hot milk, and parsley into mashed potatoes and beat until smooth.
Cook chopped apple with 1 tablespoon of water in a covered pan until it becomes a pulp.
Serve colcannon with a knob of butter, three sausages, and apple sauce.