Direct heat cooking is generally used when cooking smaller pieces of meat that takes less than half an hour to cook.
Direct heat can also be used to sear your meat to get those browning lines and texture before transferring to cook at a lower temperature. This is the most common and “standard” method of cooking, which is to simply place your meat over a direct source of fire (such as on your cooking grates).
Indirect heat cooking is used when cooking bigger pieces of meat that take more than half an hour to cook. Common examples include legs of lambs, turkeys and whole chickens. The objective of indirect heat cooking, as the name suggests, is to ensure you are not cooking directly above a source of heat. It is important to use indirect heat for the suggested meat because it keeps the flavors and juices of the meat intact.
How to perform indirect methods of cooking:
For charcoal grills, use aluminum tray or charcoal holders to separate the coal to one side of the grill (simply push them to the periphery if you like). Cook meat away from the coal, rather than directly above it. Use air vents on the grill cover to regulate heat.
In the case of gas grills, it is actually even easier to control the heat for indirect cooking method. Try to look for grills with individual burner bars separate heat control knobs. Preferably a grill with three burners. Turn off the centre burner and use only the side burners. Meat should be placed in centre of grill away from the side burners. In doing so, you can perform both direct and indirect cooking at the same time, which is really useful if you want to cook a lamb’s leg and some crabsticks at the same time.
Some points to note:
For burgers, crabsticks, thin fillets, meat balls and other similar processed food, direct heat is used
Indirect heat is important for lambs, whole chicken and generally big chunks of meat like turkeys.
Indirect cooking can only work with grills that have a cover
Temperatures for indirect cooking should ideally be around 225 F to 275 F. Whole chickens and turkeys may require higher temperatures of up to 300 F.