When you are making these eggplant parmesan rollups you want the eggplant slices really thin so that it rolls well. If you have good knife skills, you can cut the slices by hand. If you are like most people, me included, it can be hard to get the slices thin and even. That is when a mandolin comes in. The slicer makes it much easier and faster to get the eggplant sliced thin. I recommend using a mandolin with a hand guard to protect your fingers.