I have done this with a box grater, a mandolin and a food processor. All work, but the food processor wins hands down for speed and ease of use. I’d rather not think about how many times I’ve skinned my knuckles on a manual method LOL. Whatever you do, do not buy the pre-cut pieces of carrot, sometimes called matchsticks. I tried them once and hated the result. The pieces are thicker than a grater will produce, plus the carrot becomes more dried out. It does not bake up the same. At all.