Vegetables are cut in certain sizes and shapes to properly cook and look attractive. Various techniques make the task uncomplicated, all of which can be performed with a standard 8- to 11-inch chef's knife with a triangular blade, whose design makes it easy to control the blade and cutting motion.
Round Vegetable Slicing
Slicing large vegetables like heads of cabbage can be challenging. Place the knife on top of the vegetable with your hand on the top. Apply pressure to the tip of the blade and when it starts to penetrate the top, even the pressure to cut completely through the head. It may be necessary to gently rock the blade back and forth to complete the cut. To stabilize small round vegetables like onions for slicing, cut a thin slice off one side to create a flat surface. Hold the onion in place, flat surface down with one hand and use your other hand to make slices of the desired thickness. Use the full length of the blade and rock it, rather than dragging it back and forth to saw the food.
Julienne means to cut into small, matchstick pieces. To julienne a long vegetable like a carrot, first cut it into easily-controllable pieces like thirds or quarters. Once the carrot has been vertically sectioned, cut a thin slice off the side of each piece to make it lie flat. Cut the vegetable lengthwise into thin panels and stack them. Cut each stack into thin, julienne strips. For oval shapes, cut the vegetable in half vertically so there are two surfaces. Place each half flat side down and cut crescent-shaped slices. Stack the slices and cut them into matchstick-size pieces.
Bias Vegetable Slicing
To keep vegetables crisper and make them more attractive, cut them on the bias by placing the knife blade at a 45-degree angle to the food's surface. This is a common technique for cutting scallions, broccoli, celery, carrots and other long vegetables.
Dicing and Mincing Vegetables
Diced vegetables are cut into uniform cubes between 1/4- and 3/4-inches-square. If the cubes are smaller, the technique is called mincing. Cut the vegetable in half and, if it has a root end like an onion or tomato, leave that part intact to hold the vegetable together while you make evenly-spaced horizontal slices in it. When the horizontal slices have been made, cut down through the top of the vegetable to the bottom to create little squares.
Leafy vegetables and herbs like spinach and basic have thin leaves that are difficult to slice. To make the process easier, stack 10 or 12 leaves and tightly roll them into a cylinder from the long side of the leaves. Place the rolled leaves seam-side down on a cutting board and vertically cut them into thin slices using a swift rocking motion with the knife blade, while keeping its tip on the cutting surface. This creates ribbons or chiffonade.