I know most of you know how to make a sandwich but I figured I use as much detail as possible anyway - just for the fun of it. Besides, I'm at work and have nothing better to do anyway.
Drain and press tofu to get rid of the liquid. Cut off 2 thick slices per sandwich (if you're not a big fan of tofu just use thinner slices and you'll hardly know its there). Bake the slices at 450 degrees for 15 minutes -or don't.
While that's going on, put 2 pieces of bread in the toaster and slice your tomato and onion (I like two slices of tomato and one slice of onion per sandwich). Cut your soft, ripe avocado in half and put the half with the pit in it away for later - make guacamole or something. Ok, now take the half you're using for this sandwich and with a butter knife spread a bit of it on both pieces of vegan bread. The bean sprouts will stick nicely to this. (I like avocado and sprouts on both the top and bottom of my sandwich, but if you're watching your fat and/or calories or just don't like so much avocado and sprouts, just make up one slice of the bread).
Take the tofu out of the oven and put 2 slices on one of the pieces of vegan bread with avocado and sprouts, and top with tomato, onion, and second slice of bread (or make some extra slices of tofu, tomato, and onion and eat as an open sandwich).
I'm sure other veggies would be super with this sandwich as well, howe'ver, I'm not very creative (in the kitchen), so feel free to offer suggestions. :)