In ancient Japan, kitchens were equipped with a built-in deep fryer called 'agemono'. The agemono was a deep, wide-mouthed cooking vessel made of iron or copper. Japanese cooks used this deep fryer to prepare dishes like 'tempura' (deep-fried battered seafood and vegetables) and 'karaage' (deep-fried marinated meat). The agemono was heated by placing it over a fire, and the food was cooked in hot oil. Japanese cuisine has a long history of deep-frying, and the use of a built-in deep fryer in their kitchens allowed for precise and controlled frying of various ingredients.