The tandoor is a cylindrical clay oven reaching 480°C+ at its walls. Food is exposed to three types of heat simultaneously: direct radiant heat from the charcoal, conducted heat from the clay walls, and convective heat from the rising hot air. This triple-heat exposure is what gives tandoori food its characteristic charred exterior and juicy interior in minutes. The extreme temperature also causes the rapid Maillard reaction that produces the signature smoky, slightly bitter, deeply flavoured crust.
Meats are marinated in yogurt-based mixtures — the lactic acid tenderises the surface while the proteins in yogurt promote browning. Naan is slapped directly onto the clay wall where it sticks, bakes from conducted heat on one side and radiant heat on the other, developing char spots and puffing with steam. Temperature differential is extreme: 480°C walls with food spending only 3-8 minutes inside. The yogurt marinade is always the second marinade — the first is a spice paste rubbed on the meat for initial flavouring.
For home tandoori: marinate overnight, bring to room temperature, cook on the highest rack of your oven with the broiler on maximum, on a preheated cast iron pan or pizza stone. A kamado grill (Big Green Egg style) is the closest home equivalent to a tandoor. The red colour in restaurant tandoori chicken is food colouring — traditionally it comes from Kashmiri chilli, which gives vivid red without excessive heat.
Marinating without the initial spice rub — the yogurt layer goes on top. Using Greek yogurt — too thick, doesn't coat evenly. Over-marinating in yogurt — more than 8 hours and the surface becomes mushy. Trying to replicate in a conventional oven at 200°C — you need maximum heat (260°C+) and a pizza stone at minimum. Not allowing the tandoor to heat for 1-2 hours before cooking.