1. Score the cod skin with a knife in 2 or 3 places, sprinkle with a little salt and pepper and set aside for 15 minutes.
2. Add the mayonnaise to the miso and mix well. (If it’s difficult to mix them, add a little milk)
3. Melt the olive oil and butter in a frying pan, and fry the cod skin-side first over medium heat.
4. Fry until the skin is lightly browned and the fish is cooked two-thirds of the way through. Flip over and lightly cook the other side, then quickly flip back and spoon over the miso mayonnaise. When everything is fully cooked, sprinkle with parsley and serve.