Cut fish into portion pieces and fry in butter.

Cut onion into rings, sautee in butter, pour with beer, bring it to boil, salt and pepper. Then add prepared blackhead and stew for 5 minutes.

Mix milk with starch and yolk, pour the mixture in beer, add bay leaf and stew for additional 5 minutes.

When serving, season with chopped greens, garnish with fried turnips.