Dice the onion and saute in 10g (approx. 1 tablespoon) butter. Set aside.

Clean and slice the mushrooms into small pieces. Saute in the remainder of the butter. Set aside.

Peel the potatoes and cut into cubes or slices.

Bring to boil the water in a large saucepan, add salt and the potatoes. Cook until almost done.

Add the sauted onion and mushrooms to the pot with the potatoes and water. Add the milk. Bring gently to the boil then turn down to a simmer until the potatoes are done.

Serving

Serve straight from the pot as is, or try topped with sour cream.