A couple of weeks back, I said that if ramen is like the hamburger of Japan, then gyudon (simmered beef and rice bowl) is its hot dog. Extending the analogy, I'd say that oyakodon is its pizza—if pizza were the kind of soul-satisfying comfort food that's easy to make at home from scratch, with minimal ingredients, in about 20 minutes. With the intense heat we've been getting on the San Francisco Peninsula in the past few weeks, and my equally intense schedule lately, these quick and easy one-pot rice bowls have been a huge time-saver for me in the kitchen.
In Japanese, oya means "parent," and ko means "child." Donburi, typically shortened to just don, means "bowl," though, like "paella" or "casserole," it's also the name of any dish served in a donburi. These dishes are frequently (but not always) composed of ingredients simmered together in broth, then poured over rice. In this case, the oya and the ko are chicken and egg.
To make it, I start with the classic Japanese sweet-and-savory combination of dashi, soy sauce, sake (make sure to use a dry one), and sugar. Some folks use mirin instead of sake; either will work. After combining these ingredients in a saucepan and bringing the mixture to a simmer, I add a thinly sliced onion. If you want to get all fancy or plan on making this a lot, you can spring for a donburi pan, a small, saucer-like skillet designed specifically for simmering ingredients destined for rice-topping. Otherwise, a skillet will do fine. (You'll just have to squish the ingredients around a bit to get them to fit perfectly on top of a bowl of rice.)
I like to use a little bit more broth than is typical—I start with about a cup for every three eggs—because I like to simmer it down to tenderize the onion and to concentrate the flavor of the stock. I find that cooking the onions for a full five minutes at a hard simmer before adding some thinly sliced chicken gives them plenty of time to tenderize.
I also like to use boneless, skinless chicken thighs, which stay juicy as they simmer, though you can easily use chicken breast if you prefer. Just be sure to slice the chicken thin so that it cooks rapidly, and don't let it overcook! Five to seven minutes is plenty of time for thighs, and three to four minutes should do for breast.
Once the chicken is cooked through, I add some sliced scallions. If you can get your hands on mitsuba, this is the place to use it. It's a Japanese herb that looks and tastes a bit like parsley, but the flavor is much milder. The aroma reminds me a little of watercress, but without any of the pepperiness. It won't make or break the dish, but it's nice to have if you can find it.
Next, I add eggs. The key here is to not over-beat them. You want to see distinct sections of egg white and yolk. Chopsticks are my favorite tool for beating eggs like this, and the chopsticks can then be used to drizzle the eggs into the simmering broth (see the video above). Traditionally, you'd cover and simmer the eggs until they're about half set, though nobody is stopping you from cooking them however you like them. Once the eggs are cooked, I pour the contents of the pan over rice. There will be quite a bit of extra juice. This is fine. It should soak into the rice and flavor the entire bowl.
Personally, I like to mix things up a bit by adding an extra egg white to the beaten eggs, reserving the yolk, cooking the oyako to medium, then adding the extra raw egg yolks back to the top of the bowl for mixing in.
But that's just me.