Photograph: Dan Jones
Melt the butter in a pan, add the leeks, cover and cook for 10-15 minutes until soft. Meanwhile, cook the quails' eggs in boiling water for 2 minutes, then drain them.
Add the diced potato and stock to the softened leeks and simmer for 10-15 minutes until the potato pieces are tender. Meanwhile, put the haddock in a frying pan, cover with the milk, add the bay leaf and simmer gently, covered, for 8-10 minutes, until the fish is cooked through.
Drain the fish (make sure you keep the milk). Flake the fish and peel and halve the quails' eggs. Add the poaching milk and the flaked fish to the pan of potatoes and leeks. Simmer together briefly, then stir in the chopped parsley and some freshly ground black pepper; check the seasoning. Serve the soup in warmed bowls, topped with the halved quails' eggs. Serve with buttered soda bread.