Prepare the Rice Rinse white rice under running water until the water is almost clear and drain the rice well. 

Wash the mushrooms I know everyone says don’t wash mushrooms, but for matsutakes I do. They are very sandy. Just dry them off well. Trim off the bottom of the stems which are usually covered in hard packed dirt. (I peel around the bottom of the stem with a sharp knife). Again, thoroughly wipe the mushroom with a damp towel or paper towel. You do not want to eat rice with any grit.

Slice small mushrooms in half lengthwise and then into thin slices. For larger mushrooms, cut off the caps and then cut the mushrooms in half or thirds before slicing, keeping the mushrooms around the same size.

Making the rice with a pot Choose a smallish heavy pot with a tight fitting lid, around 2-3 quarts. Put the well-drained rice, dashi, soy sauce, mirin, and sake into the pot. Gently stir to combine. Add the matsutake mushroom on top of the rice (do not mix the mushrooms into the rice which will cause the rice to cook unevenly) and let the rice sit for 15-30 minutes to ensure the rice is fully hydrated and will yield the best consistency.

Turn the heat to medium and let the rice come to a simmer. As soon as it simmers, cover the pot with a lid, turn the heat to medium low, and cook for 10 minutes. Lower  the heat to the lowest setting and cook for an additional 10 minutes. Turn the heat off and let the rice sit for an additional 5 minutes before mixing it gently so the mushrooms are evenly distributed. Taste the rice and season with a little salt if needed. Portion into rice bowls and garnish with a little scallion if desired.

Making the rice with a rice cooker Put the well-drained rice, soy sauce, mirin, and sake into the cooking pot. Gently stir to combine. Add the dashi to the 2-cup water line of the inner pot; depending on how well the rice is drained, how much moisture the rice contains, you may need to add a little more or less dashi (you can use water if you don’t have any more dashi). Add the matsutake mushroom on top of the rice (do not mix the mushrooms into the rice which will cause the rice to cook unevenly). Newer rice cookers include 10 minutes of soaking time before cooking; however, to make sure rice is fully hydrated and to get the best consistency, I recommend soaking the rice for 15–30 minutes before cooking. Then push the start button.

Once the rice is done cooking, let the rice sit for an additional 5 minutes before mixing it gently. Taste the rice and season with a little salt if needed. Portion into rice bowls and garnish with a little scallion if desired.