Chop the zucchini, red pepper and carrots into small cubes. Add to a large, deep bowl and pour a little oil and salt. Stir to coat all the pieces evenly with oil and salt. Add them to the baking pan and arrange them so that they do not touch each other. Have space from each piece of vegetable to another. This allows the vegetables to be crispy and baked on all sides. Bake for 20-30 minutes (depending on how many pieces there are). If necessary, check from time to time and, stir to bake evenly.