Masa

Start off by thinly slicing the onions, and cutting rockbird meat into large, bite-sized pieces.
Next, crack open an egg, and lightly scramble it.
Then, after making a stock in the frying pan with water, dashi soy sauce, mirin, and sugar, heat over a fire. (I find this step annoying, so I always end up using dashi soy sauce. Dashi soy sauce is super convenient.)
When the mixture starts to boil, throw in the onions and rockbird meat. Once the onions and rockbird meat are thoroughly heated, throw in half of the scrambled egg and cook over low heat.
Once the egg has solidified, add in the rest of the scrambled egg, and turn off the heat.
After the residual heat has passed through the rest of the egg, the soft-boiled gooey oyakodon is complete.
All that’s left is to heap it on a bowl of freshly cooked rice.