Mise en place (MEEZ ahn plahs) is something that virtually every cooking blog and commercial website is obligated to cover, just because it’s so damn useful.
No, this is not me busting out my incredibly limited French just to be pretentious or to indulge my inner snob — “mise en place” (or “mise,” as shortened by the venerable Ming Tsai) is a French term that means to “set/put in place.” It’s about taking a little time to make sure you have all of your ingredients and tools ready to go before you start cooking.
Having everything in place before you commit food to pan means having ingredients measured and cut, oven pre-heated and pans and utensils at hand. You shouldn’t really be mixing or cutting anything at this stage unless it’s absolutely essential. That way, you can focus on the act of cooking — controlling heat levels, timing and seasoning — and it keeps your attention on the stove, reducing the risk of accidents and the chance that something will burn or boil over.
I know chefs and cooks on TV peel vegetables and slice meat in front of the camera, but that’s mostly for demonstration purposes, to show how they handle the ingredients. Look closely and you’ll see that what they’re cutting is a small amount compared to what’s already been prepared and waiting in a bowl.
You see me use this concept in the ingredient snapshots I provide with my recipes — nearly everything I intend to use in a dish has been measured, cut and placed in bowls, ready for me use. The only exceptions are last-second substitutions or omissions that I tell you about anyway in my annotations. Some would extend the idea to measuring and pouring out liquid ingredients, but that takes up so little time that I don’t bother.
For more info, check out the explanations at The Reluctant Gourmet and Molly’s Menu. They’re detailed and easy to read, having been written by cooks with a lot more experience than I do.