Get the tofu out and gently squeeze some water out of it using paper towels or cheesecloth. Set it on a plate to dry out a bit. Chop the zucchini into pieces and put them in a colander and sprinkle with salt. (This draws some water out and make them brown more nicely.) Slice the bell peppers, and cut the carrots into matchsticks. Mince your garlic and ginger if you're not being lazy (like me) and using the inferior powdered variety.
Cut your tofu into 1 inch cubes. Put in a bowl with the corn starch and a good pinch of salt and pepper, stir to coat. Set aside.
Set a large, deep skillet or wok on just a notch or two below high heat. When it's hot add half of the oil, swirl it around, and then half the garlic and ginger (unless you're using powdered, then add after the veggies). Wait a few seconds, turn the heat all the way up, and then toss all those veggies you chopped up into the skillet and cook, stirring, until they brown nicely, a few minutes.
Try a carrot piece. If it's crunchier than you'd like, add about half a cup of water and wait until it boils off. Transfer everything to a plate.
Turn the heat down to medium and add the remainder of the oil. Wait until it's hot and then add the garlic and ginger (again, if you're using powdered, just sprinkle on top after adding the tofu). Turn the heat back up and add the tofu. Cook, stirring, until browned nicely on all sides.
Turn the heat down to medium. Add the veggies and any juices back to the skillet. Add soy sauce and roasted sesame oil if you've got it. Add a little water if it's dry and cook for a minute or two until the liquid is reduced and all the tofu has dislodged from the bottom of the pan. Sprinkle with salt and pepper to taste. Serve on rice.