2. In small bowl, beat eggs with fork.
3. Add grated cheese, onion, and the dry mustard; stir until they are well blended.
4. Trim crust from bread; cut each slice into quarters, to make 24 squares in all.
5. Arrange in shallow baking pan.
6. Spoon heaping teaspoonful cheese mixture on center of each bread square. Top each with a piece of bacon.
7. Bake 15 minutes, or until bread is toasted and topping is slightly puffed.
8. Serve hot . This recipe makes 2 dozen puffs.