1) Make 1/2-inxh thick slices of tomato and sprinkle sugar over them.
2) In a pie plat, combine mustard, salt and flour.
3) In a cup, put 2 tablespoons of flour mixture and set aside.
4) In the remaining flour mixture, dip the tomatoes slices and coat well.
5) In a large frying pan, in butter or margarine, sautÃ© the tomatoes slices, few at a time until golden brown.
6) In a heated serving platter, arrange the drained tomato slices. Keep them warm.
7) In pan drippings, add 2 tablespoons of flour mixture and combine with milk.
8) Cook the gravy until thickens and boil for 1 minute, while stirring continuously.
9) Pour the gravy over tomatoes.
10) Garnish with parsley, if liked and serve warm as side dish.