Heat the waffles in the microwave, about five or ten seconds on each side. You want it to be mostly defrosted, but not totally hot.
Whisk the egg white and soymilk in a small bowl, and add cinnamon and Splenda to taste.
Dip each waffle in the egg mixture, making sure to get the egg into the nooks in the waffles. Sprinkle each side of the waffles with some more cinnamon and sugar, and cook over medium heat in a nonstick pan sprayed with cooking spray for about five minutes, or until nicely browned.
Sprinkle with more cinnamon and Splenda to serve, if desired.