Takikomi Gohan (also known as Gomoku Gohan) literally translates to "cooked with rice". It's basically rice cooked in stock with stuff in it, like a pilaf. In Japanese groceries you'll usually find a whole section of instant packets that you just add to rice before you cook it, but they often contain loads of MSG. It's fairly simple to make from scratch and you can add all sorts of things like burdock, carrots, wild mushrooms, etc.
I strongly suggest you use a rice cooker to make this. While you could make this on the stove in theory, I'm so reliant on a rice cooker I'm not sure how much liquid to use or what heat to cook it over, so you're on your own there. If you've cooked rice on a stove before please do post your tips in the comments.
- Rinse the rice until the water runs almost clear, then drain as much of the water out as you can.
- Add the sake and reserved crab liquid. Fill the rice cooker bowl up to the "2" mark with dashi.
- Add the crab, bamboo, and mushrooms. Stir the liquid and taste for salt. It should taste like a slightly watery soup. Add more salt if needed.
- Run the rice cooker according to directions. When the rice is done and has had a chance to steam, add the mitsuba and gently fold into the cooked rice.
- Garnish with salmon roe and serve immediately.