Fera Fish

On my way back from the office, I stopped at the super market, bought 2 mangoes, a few tomatoes, a cucumber, and then went to look at what was available at the fish department. I bought a fish lake typical around the Geneva Lake. In French it's called "Fera", in English I don't know as according too Wikipedia it lives only in the Geneva Lake... love this fish, in fact I love all fishes, but this one has a very subtle taste.
When I arrived at home, I had a problem as I have often eaten Fera at restaurants, but never cooked it before, and as always I googlise it to find a recipe that suited me. The original one is here, in fact it's only the sauce recipe I was looking for, and here is the recipe I prepared for myself.
Ingredients for 1:
1/2 fillet of Fera (200gr)
1 French shallot 1 big carott
1/2 cup white wine
1/4 cup white balsamic vinegar
5 sticks chives
30gr butter
1 tbs creme fraiche (optional)
Chop the shallot and the carrot and put them in the white wine and vinegar with some salt and pepper and reduced to one quarter (approx. 10mn), then add the butter (very cold and cut in cubes, and stir. Add the crème fraiche.
In a separate pan heat a little bit of butter with 1tbs olive oil (you can use corn or any kind if you like) and cook the fish for 2 minutes on each side. Serve in a plate, pour the sauce and serve with some rice. Decorate with the chives.
Bon Appetit !