How to Grate Tomatoes: This is one of the great rustic techniques of the Greek kitchen. Have ready a hand grater, preferably one with coarse teeth. Make sure the tomatoes are washed and dried. Hold the grater over a plate or shallow bowl. Hold each tomato from the stem end and grate it along the coarse openings of the grater until all that remains is the tomato's skin, flat and wide open. What you are left with are the pulp, the seeds, and the juice. As for the seeds, most traditional cooks aren't bothered by them.