Zander with polenta, black trumpet puree, rocket beurre blanc and white asparagus sabayon

Probaly, I have mentioned already that once in a while I like to give a new chance to products that I actually don't like at all. Yesterday, I found beautifully fresh rocket salad in a farmer's shop and I just couldn't resist, altough it is really not my cup of tea. It was a good idea to go for it once more, because I kinda liked it in the beurre blanc, however the satueed leaves on top of the fish were just to much for me, however it is definetly something for those who like rocket. If beurre blanc then fish is not far! This time a nice zander filet made it onto the plate with black trumpet puree, white asparagus sabayon and polenta. I hope nobody throws away the peel and the ends of white asparagus, because it is the perfect base for a soup or sauce.

Ingredients:
for the polenta:
42 g white polenta
200 ml vegetable stock
1-2 tablespoons freshly grated parmesan
10 g butter
15 g milk
salt, pepper
for the rocket beurre blanc:
1 shallot
10 g butter
4 tablespoons white wine
1 teaspoon white wine vinegar
200 ml fish stock (optional)
150 g ice cold butter
25 g rocket
salt, pepper
for the black trumpet puree:
20 g dried black trumpet
1 teaspoon butter
1 shallot
100 ml vegetable or poultry stock
35 g butter
1 twig thyme
few drops of lemon juice
salt, pepper
for the white asparagus sabayon:
100 ml asparagus stock
50 ml white wine
1 shallot
1 egg yolk
few drops of lemon juice
nutmeg

In case you cook normal polenta, then follow the instructions on your package. Otherwise bring stock to the boil, stir in the white polenta and cook for 30-40 minutes while stirring all the time. When cooked stir in the parmesan, butter and cream, season. Pour it into any kind of form and let it cool. Before serving slice polenta and fry in butter until golden brown. For the rocket beurre blanc melt butter, add chopped shallot, then the wine, vinegar and the stock. Cook until there is about 1/4 left. Now blend it with the butter and rocket, season. For the mushroom puree sautee chopped shallot in butter, add the previously soaked black trumpet and the stock and cook for about 15-20 minutes. Puree together with the liquid, butter and thyme leaves, then puree. Put it back onto the stove and "dry" over low heat for about 10 minutes. Season with salt, pepper and a few drops of lemon juice. For the sabayon reduce asparagus stock with wine together with chopped shallot and some leftover asparagus ends and peel. Add egg yolk and mix together, then beat it over steam until foamy. Season with salt, pepper, nutmeg and a few drops of lemon juice. Season with seared zander, green asparagus and in butter sauteed rocket.