Oyakodon is a rice bowl dish with chicken, onion and egg. It is one of the major rice bowl, which you can find at throughout Japan. Not only at ordinary diners, but also served at diners specialized in soba or udon noodles and high end restaurants.
Chopped chicken is cooked in a broth based on soy sauce together with sliced onions in a special flat rice bowl pot. It is not pan fried but stewed. Then, beaten egg are put into the pot. Then, all ingredients inside the pot are put on the hot rice and lid is put on the bowl.
Then, the most important thing of oyakodon is the name. Don means bowl and oyako means parent and child. Why parent and child? Parent is a chicken and child is an egg.