as promised:

Ingredients (for 4 persons):

1 big onion
1 spring onion (green onion, salad onion)
1 green paprika
About 9 ounces (oz) ( 250 gram) mushrooms in thin slices
2 ounce butter
14 ounce of Cod (fish)
Pepper, paprikapowder,
2 spoons of flour
3 spoons of breadcrumbs
For the sauce:
0,5 ounce of butter
1 big spoon of flour
About 7 fl oz of milk
2 teaspoons of bouillon (in powder form)
1 spoon mustard
7 fl oz of yoghurt
Pepper

First cut the onion, the paprika and the spring onion in little pieces. Cut the mushrooms in little slices. Put some butter in a pan and bake the onion and spring onion for 1 minute. Add paprika and mushrooms and stew for another 3 minutes. Wash the fish and dry with kitchen paper. Cover the fish with pepper, paprikapowder and flour. Grease a baking dish a bit and put in half of the vegetables. Put in the fish and cover with the second part of the vegetables. For the sauce melt an ounce of butter in a saucepan and stir with flour. Add while stirring the milk till a smooth sauce. Take the pan from heat and add mustard and yoghurt till again a nice sauce comes up. Put the sauce over the fish with vegetables.
Spread the breadcrums over it and put some butter on it as well. Put the dish in an oven and let it heat for about 25 minutes. Nice to serve with rice.

Have a nice meal.