Clean the mushrooms and, depending on the size, cut them or leave them whole. Whole pieces shouldn`t be more than 2 cm hat width, otherwise they won`t be cooked through afterwards.
Heat the oil in a pan, fry the mushrooms in it, if available, put the lid on, stir from time to time.
Dissolve the broth in the hot water. Melt margarine in a saucepan, add flour and stir until smooth. Deglaze with broth, stir well, simmer. Add the cream, bring to the boil. Add the mushrooms with the liquid. To taste.