To cut sweet potatoes, scrub and dry them, then trim a thin slice from one side to make a stable base. Mississippi State Extension recommends creating a flat surface on round foods; lay this side down and cut the potato into planks. For sticks or cubes, continue from the planks; for wedges, halve a section lengthwise and cut each half lengthwise. If the recipe calls for peeled pieces, use a vegetable peeler on the stable potato. The University of Illinois Extension handout supports scrubbing, peeling and cutting to recipe size. For regular potatoes, use our guide to fries, cubes and wedges.
Prepare the potato and board
Use a chef’s knife, a stable board, and enough counter space to keep cut pieces away from the blade. If peeling, use a peeler before cutting or peel each stable section after splitting it; do not hold a round potato in the air while using a knife to peel it. Skin-on pieces work for many preparations, but follow your recipe if it specifies peeled pieces.
Place the potato lengthwise and cut a thin slice from one side. Turn it so the new flat face rests on the board. This gives you a steady reference face and stops the tuber rolling while you work. If it still rocks, reset it on a broader flat face or trim a small amount from the side touching the board.
Make planks, then choose a shape
- Cut manageable lengths. If the potato is long, divide it into sections that fit comfortably on the board. Keep the guiding fingertips curled and the thumb tucked back.
- Make planks. Stand each section on the flat face and slice lengthwise into slabs. Match their thickness to the cut: thicker planks make substantial fries; thinner planks make narrower sticks or smaller cubes.
- Finish the shape. For sticks, lay a plank flat and cut lengthwise at even intervals. For cubes, turn the sticks a quarter-turn and cut across them. For wedges, halve a potato section lengthwise, put one half cut-side down, then cut lengthwise into wedges. Keep each cut face stable on the board.
Similar-sized pieces are useful when a recipe asks them to cook at roughly the same pace. There is no universal size: use the recipe’s dimensions, or make pieces similar to one another when it gives none. Utah State University Extension lists familiar small, medium and large dice and stick cuts; these terms help describe shape, while the recipe remains the final guide.
When a cut becomes difficult
Sweet potatoes can be dense. Keep the board stable and use a sharp knife with a smooth, controlled cut. Do not put your palm on top of the blade or force a knife that has stopped moving. If the blade binds, stop, keep your fingers clear, and withdraw it along the entry path if it moves freely. Then make the section smaller or reset it on a wider flat face. Our guide to why a knife can wedge in dense vegetables explains the difference between wedging, a dull edge and food sticking to the blade.
Move pieces with a scraper or the broad side of the knife, keeping the edge away from your hand. If you prepare vegetables often, our santoku-versus-nakiri guide explains how a general-purpose knife and vegetable specialist suit different repeated cuts.