Salt and rub the cleaned carp portions with lemon juice. Line the prepared baking dish with butter slices, place the fish portions on it and sprinkle them lightly with cumin. Preheat the oven to 180 degrees.
Place the baking dish in the preheated oven and baste the fish with the baked juices while it is baking. If necessary, the carp can be basted with a little water. The baking time depends on the thickness of the portions and the type of oven.
The finished fish can be served with mashed potatoes.