Work the flour, eggs, salt and mineral water into a firm dough and place in the spaetzle press. Press the spaetzle into hot water. When they swim up, fish off with the slotted spoon.
Cut the mushrooms and bacon and fry them together. Add the spaetzle and deglaze with the cream. Season the sauce to taste. Stir in the mountain cheese and let it melt with the lid closed. Then serve.