The most popular Indian dishes are those cooked over a blazing fire in the so-called tandoor, a cylindrical open-top clay oven fueled by wood or charcoal. The tandoori technique evolved from an old Middle Eastern method of baking bread, which spread to other parts of the continent, including northwestern India, where people began experimenting with cooking meats and other foods in tandoors, adding special marinades and spice rubs, both of which are now integral parts of Indian-style tandoori cooking.
The marinade used in most tandoori dishes starts with yogurt; it holds well to the meat, lends a note of mild acidity, and keeps the herbs and spices in place. Even though the clay ovens themselves impart a special flavor to the food, most of it comes from the traditional combination of spices.
Tandoori dishes are typically either intensely red or yellow colored, depending on the marinade ingredients: the red is provided by ground annatto seeds, while the yellow comes from saffron or turmeric. In addition, tandoori dishes are also traditionally flavored with ginger, garlic, coriander, cayenne pepper, and a combination of roasted and ground cardamom, cumin, cinnamon, cloves, nutmeg and black pepper called garam masala.