1. Combine flour, cornmeal, and salt. 2. Wash and core the tomatoes. Slice about 1/4" thick, discarding end pieces. Coat each slice with flour and cornmeal mixture. 3. Heat oil with the butter over medium heat. Fry the prepared slices in the hot oil, using a spatula carefully to turn each slice. When brown on both sides, sprinkle very lightly with sugar and pepper and serve immediately.