I used to go to an Indian restaurant that had the most tender chicken I've ever had. In general, it seems like Indian curries have very tender chicken. Could somebody explain if there is a secret? Is it marinading in yogurt, the tandoor, an industrial tenderizing agent? The closest I've ever achieved is in a recipe I have where chicken is marinaded and cooked with pineapple. I know pineapple contains a protease enzyme which helps tenderize meat, and in extreme situations, will entirely dissolve shellfish proteins. Is there a spice or something that is used in Indian food that works similarly?
It is a combination of the marinade (with yoghurt and lemon juice probably being the main factors in the tenderness) and the hot, fast cooking in the tandoor, further enhanced by the use of metal skewers which conduct the heat to the middle of the meat quickly. A good tandoor chef will time the cooking perfectly so that the meat is safely cooked but hasn't dried out.