Remove stem end of tomatoes with sharp knife. Cut out center portion of each tomato, leaving cavity large enough to hold 1 egg. Reserve cut-out portions.
Place hollowed-out tomatoes in bottom of well-buttered, deep baking dish. Carefully break each egg and place in hollow of tomato. Sprinkle lightly with salt and pepper. Place in 375° oven 10 minutes or until egg is set and firm in center of tomatoes.
Chop reserved inside portions of tomatoes finely. saute bacon until crisp and golden brown. Drain on absorbent toweling and crumble. Mix bacon and chopped tomato pulp. Place spoonful of mixture on top of each baked egg. Sprinkle each top with portion of Parmesan cheese.
Place under broiler about 6 inches away from heat until cheese has just turned golden brown. Serve at once, piping hot.