I was at a terribly important lunch meeting yesterday, and one of the people I met with, Jennifer, asked me about the chicken at a restaurant. "How do they make such good chicken?" I suggested that they were good at making chicken. It wasn't until a little later that I realized what a thoroughly unsatisfying answer that was. Sorry, Jennifer.
You see, strictly speaking, I was being both concise and complete, but, uh, only if you already knew what I was talking about. You see, roasting chicken is Very Simple. There are very few ingredients necessary (chicken, salt, and some sort of fat), The technique is likewise Very Simple. You heat an oven, put the chicken in, and take it out when it's done. See? Simple.
The problem is that Very Simple is cooking code for If You Mess Anything Up You Will Ruin The Dish. Okay, maybe it's not so bad, but the fewer ingredients and steps you have, the more impact each of those ingredients and steps will have on the final product.
This is what I meant by the restaurant being very good at the chicken. They have some experience at making it, and know what to look for as far as it being done. They know their equipment and their timing, and they have a good grasp of how to maintain consistency. This particular restaurant spices its chicken a bit more than I mentioned above, so it has a bit of leeway, but they do a good job with the roasting.
To maximize your success, start with the ingredients. You want a quality chicken, a good butter or olive oil, and some decent kosher or sea salt. Before you cook the chicken, you need to bring it up to room temperature.
The difficult part of roasting a chicken is that there are two different kinds of meat that cook at two different rates. If you cook the white meat to the right temperature, then the dark may be undercooked and dangerous to eat. If you cook the dark meat to perfection, you might dry out the white meat. Most of the techniques are to ensure that you bring both parts of the chicken to the same temperature at the same time, including the technique of bringing the meat up to room temperature before cooking it.
The shorter a thermal distance the chicken has to go before it's cooked, the easier it will be to bring both sides to temperature together. The dark meat takes longer to cook because there is more fat in the dark meat than there is in the white meat, and the fat acts as an insulator for a while. If the fat in the chicken is still cold, then it will take the dark meat relatively longer to cook. If the chicken starts out at room temperature, the insulating effect of the fat will have less effect.
Another technique I like from Bittman is to heat the oven to 450°F, and five minutes after you start the preheating, put in an oven-proof skillet (such as one made of cast iron) that is big enough to hold the chicken. This preheating of the skillet will transfer more heat into the dark meat, which will be resting on the skillet, saving the white meat from overcooking.
While everything is preheating, you cover the chicken with olive oil or butter, which will cause heat to more effectively cook the skin of the chicken. Aside from the meat cooking properly, a crispy, dark skin is the most important goal of the roasted chicken. It't the part everyone will see first, and it adds a great texture to the food. Plus: it's tasty. After you've lubed the chicken, liberally salt it, because if you don't season the chicken, it won't taste of anything (not even chicken).
Once the oven is preheated, put the chicken into the pan breast side up. Be careful not to burn yourself. Now put the chicken in the oven and don't touch it for 40 or 50 minutes. If you peek through the oven window and notice that one side is cooking faster than the other, you can turn it 180° at about the 30-minute mark. Other than that: no touching.
Once it seems ready, take the temperature of the chicken in the thigh, and if it's reached 160°F (See the picture after these chicken roasting tips for an example, but ignore tip #2 if you are following this method), then you can probably take it out. Another useful metric is to tip the chicken so the juices inside run out into the pan. If the juices are clear, the chicken is good. If they're pink, put the chicken in for longer.
Let the chicken rest. Carve, and enjoy.