あら refers to the remaining parts of the fish after removing the flesh, such as the head and bones. Cooking refers to dishes stewed with soy sauce and sugar. Taki (食き) is the noun form of taku (食く), meaning to cook or cook. It is mainly made of sea bream or yellowtail, cooked with ginger or green onion to remove the fishy smell. You can often see it served as a side dish at izakaya. It is also called あら煮.