To make the gubbröra, heat a frying pan over medium heat and add the butter. Once hot add the cod fillets and cook on each side for 4–5 minutes.
While the cod is cooking, in a bowl combine the eggs, potatoes, Swedish anchovies, crème fraîche, mayonnaise, dill and chives. Season with salt, pepper, and a bit of anchovy brine for extra flavour.
To make the horseradish potatoes, boil the potatoes for 15–20 minutes until tender.
Press them while hot, leaving the skins on if possible.
Stir in the butter and grated horseradish, adjusting to taste if you wish. Season with salt, pepper, and add a splash of crème fraîche or cream if you like it creamier.
To make the browned butter, melt the butter in a saucepan. Once it stops foaming and the milk solids turn golden, remove from the heat.
Serve the cod alongside the gubbröra, with the horseradish potatoes and browned butter in separate serving dishes.
