Chop onion, green pepper, grated carrot and slice mushrooms.  Sauté the vegetables in the water or stock, in a large frying pan until most of the liquid is gone and the vegetables are soft.

Mix the remaining ingredients together in a bowl, adding a bit more water if you wish, will make a thinner sauce.  Add to the vegetables in the pan.  Mix well and cook, stirring over low heat for about a minute until thickened.

Serve poured over hot, split baked potatoes with a crisp green salad.