Preparation:
cut 1/2-inch from the top of each tomato scoop out seeds and core sprinkle inside of shells with salt and pepper invert onto paper towels to drain heat butter in a saucepan, over a medium flame whisk in flour, until bubbly gradually whisk in milk heat and stir until thickened stir in mustard, cheese, and chives-mix well heat and stir until cheese melts remove from heat and allow to cool slightly gently fold in egg whites spoon into drained tomato shells set into a greased baking pan bake @ 400 degrees for 15-18 minutes, until tops are lightly browned remove from oven serve hot |