Rinse the brown rice in a sieve. In a medium or large pot, heat 2 teaspoons of the coconut or peanut oil. Add the rice. Toast the rice in the oil until it's nutty, fragrant, and dry. Add the water and a generous pinch of salt. Bring the water to a boil and reduce the heat to a simmer. Cover the pot and cook the rice for 45 to 50 minutes, until the liquid is absorbed. Remove the rice from the heat and allow it to sit for 5 minutes with the lid on. Fluff the rice with a fork, then set it aside. The rice can be prepared a day or two in advance of the stir-fry, and you can always skip this step and just use up any leftover cooked rice you've got.
Heat the remaining tablespoon of coconut oil in a large, deep skillet over medium heat. Add the onion and ginger, along with a dash of salt. Cook for about 3 to 4 minutes, or until the onion is becoming translucent. Add the shiitake mushrooms and garlic. Season the mushrooms with another dash of salt and cook until they have released all of their liquid and are soft, another 4 to 5 minutes. Add the bok choy and peas. Season the greens with a sprinkle of salt and cook for 2 to 3 minutes, until the bok choy is brightly colored and wilted.
Add the cooked rice to the skillet, along with the tamari, vinegar, and sesame oil. Fold the ingredients together and then mix them until everything is well incorporated. Check seasoning and add red pepper flakes to taste, along with any additional tamari. Divide the rice into 4 bowls and top each with a few tablespoons of chopped scallions. Serve.
Gena is a registered dietitian, recipe developer, and food blogger. She's the author of three cookbooks, including Power Plates (2017) and Food52 Vegan (2015). She enjoys cooking vegetables, making bread, and challenging herself with vegan baking projects.