In a large bowl, beat eggs until frothy, about 1 minute. Add milk and mustard. Combine the flour, baking powder and salt. Add to the egg mixture and beat until smooth. Stir in bacon, ham and cheeses. Transfer to a greased and floured 9x5-in. loaf pan., Bake, uncovered, at 350° for 55-60 minutes or until a toothpick inserted in the center comes out clean. Let stand for 10-15 minutes before cutting. Run a knife around edge of pan to remove. Slice and serve warm.