Duxelles de Champignons Recipe (Mushrooms Duxelles)

Duxelles de Champignons is a recipe from very classic French cuisine with combination of finely chopped mushrooms, shallots, and fresh parsley that are slowly cooked to a paste-like consistency. It is traditionally used in the preparation of beef Wellington, but it can also be used to flavor soups and sauces as well as to fill omelets and ravioli.
Ingredients:
200g mushrooms
50g shallots
20g butter
2g salt + Sq Fresh ground pepper
5g chopped parsley

[@robertnislick448]

Is it necessary to cover with a parchment paper lid, directly on top of the mushrooms? Or can I just cover the pot with a regular metal lid?

[@alfieboy4022]

No need for the parchment paper if you have good heat control