A recipe is meant to guide you step by step through the process of preparing a dish, but there are some basic techniques that even the best recipes don't always explain—like, how do you chop an onion or slice garlic? What's the difference between "chopped" and "minced?" Getting a grasp of some basic knife skills will instantly turn you into a better cook. If you've ever watched a chef on TV go to town on a pile of produce, transforming it all into tidy, evenly sized slices or cubes with a knife that moves so fast the blade is just a blur, it may seem like they're just showing off. But there are good, practical reasons for all of these specific cuts.
The bigger the pieces, the more time it will take to cook them. Let's say you're making a pot of minestrone and the recipe instructs you to simmer the soup for 30 minutes. That means the recipe should also direct you to cut all the vegetables to a size that will render them tender but not mushy after 30 minutes of simmering. Cut the vegetables too small and you'll end up with a pot of moosh; too big and your carrots and celery will still be crunchy.
The size and shape that you cut your ingredients into will determine the texture of your finished dish. When prepping for a batch of caramelized onions, thin slices break down and become soft, tender, and spreadable. On the other hand, if you're making onion rings, you want thicker slices that stand up to cooking and still have a nice chew to them.
The smaller you cut and ingredient, the more surface area you expose, and the more thoroughly it will become distributed throughout the dish. This is something to pay attention to when cooking with strongly flavored ingredients like garlic, shallots, onions, and ginger: large slices will diffuse a more subtle aroma through a dish, perfect for flavoring a broth—like Thai Chicken Soup (just be careful when biting into a big hunk of ginger or garlic)—whereas a fine mince will spread a bolder flavor, such as in a our luscious Lamb Curry.
Sometimes, looks do matter. When serving a dish that you made with care, the love really shines through when your knife cuts are nice and neat and the ingredients are (nearly) one uniform size. Your knife work is on full display when you're serving something like a stir fry with matchstick-sized pieces of neatly julienned vegetables or a slaw with evenly-sliced cabbage. And this is true not just with savory food—neat, even slices are what make a dessert like our Apple Slab Tart so impressive.