Grease a baking dish with ½ tbsp butter and put to one side.
Preheat the oven to 220 degrees, top/bottom heat.
Clean the fish under cold water, pat it dry, cut it into 6-8 cm pieces and drizzle the fish with the juice of a lemon. Rub the fish with 1 tablespoon of Worcester sauce.
Place the fish in the buttered baking dish and set aside.
Steam the broccoli and potatoes (to taste) until still firm to the bite.
Prepare a béchamel sauce. Now stir 2 tablespoons of mustard into the sauce. Add the dill to the mustard sauce, as well as the capers if you like them.
Take the prepared fish in the casserole dish and season it again with a pinch of salt and paprika powder.
Place the broccoli and potatoes between the fish.
Pour the mustard sauce over the cod and bake for 30 minutes at 220 degrees top/bottom heat.