Toss the ribs with the marinade ingredients and set aside for 1 hour.
When you’re ready to cook, heat 1 tablespoon oil in a wok over medium heat. Add the mushrooms and stir-fry until caramelized. Remove from the wok and set aside.
Add another tablespoon of oil to the wok (over high heat this time), and brown the marinated ribs. Once browned, turn the heat down to medium, and add the ginger, garlic, and sugar. Stir-fry for a minute, and then add the carrots, light soy sauce, and ½ cup water. Bring to a simmer and cook for 5-10 minutes, until the liquid has almost all evaporated.
While the ribs are simmering, add the rice to the rice cooker and add the proper amount of water (according to your rice cooker instructions/type of rice you’re using). This is when you can strain and add some of the liquid the mushrooms were soaking in, if desired. Alternatively, you could also use chicken, pork, or vegetable stock.
Stir in the shiitake mushrooms and 1 teaspoon salt. Shake the pot around a little so the rice and liquid is in an even layer. Spread the rib mixture over the rice. Place it into the rice cooker and press the button to start it. Your dinner is now underway.
Most rice cookers these days will tell you how many minutes are left in the cooking process. When there are 5 minutes of cooking time left, open the rice cooker lid, quickly sprinkle the peas on top, immediately cover the lid and let it finish cooking. When it’s done, serve!