Grate some fresh Romano or Parmesan over the top. Turn the heat to medium or medium high. Add the mushrooms to the bacon and fat, stir it round. Add the cabbage chunks on top of the mushrooms and generously sprinkle pepper and ground nutmeg on top. Cut the butter into pats and top the cabbage with it.
Every few minutes stir the concoction around so the butter and bacon fat covers all the cabbage.
When the cabbage is wilted and the thinner pieces are browned and the mushrooms are browned and lovely, turn the heat to low and pour about 3 tablespoons of cream over the cabbage. Stir it from the bottom to deglaze the pan of all the nice bits of flavour. The cream will turn a nice brown gravy colour and thicken slightly. You may or may not need a bit more cream. Taste for salt.