Although charcoal briquettes, wood coals straight from a campfire, and the campfire itself can all be used to cook with, high-quality charcoal briquettes, placed underneath and on top of the oven give more consistent heat. When it comes to briquettes, most campers consider Kingsford to be the best.
A good rule of thumb for cooking at a temperature of 300 to 325 degrees is to take the size of the Dutch Oven in inches and subtract three briquettes from that number to be placed beneath the oven, and add three to that number to be placed on top (on the oven lid). For example, a 12-inch Dutch Oven, requires 9 glowing briquettes beneath it, and 15 on the lid. For a 14-inch oven, place 11 briquettes beneath it, and 17 on top. Each additional briquette adds 15 to 20 degrees of heat. This rule varies with the type of food, altitude, wind conditions, and the outside air temperature, but it is a good place to start.
Remember that high altitude, cold weather, wind, and humidity all lower the cooking temperature. Thus, any of these conditions require longer cooking times or more briquettes. A wind also heats the upwind side of the Dutch Oven, requiring you to rotate the oven occasionally, or protect it with a windbreak of bricks or stones. Use fewer briquettes when cooking in the mid-day sun.
The distribution of briquettes is important too. Some recipes call for more, some for less, hot briquettes placed above and below the cooking pot, depending on how the heat needs to be distributed. Some hints follow.
- Soups, stews, or liquid dishes, require more heat (briquettes) beneath the oven than on top.
- Meat, poultry, potatoes, vegetables, and cobblers require an equal distribution of heat (briquettes) on top and bottom.
- Cakes, breads, biscuits, and cookies require more heat (briquettes) on top than beneath.
Because cast iron holds heat for a long time, food cooked in a Dutch Oven, and left in it with the lid on, will stay hot for over an hour. Simply remove all but 2 or 3 of the coals, keep the lid on, and wait until the rest of the meal is ready.