Cup of Yum
1. Gather all the ingredients.

Prepare the Ingredients

1. Discard the bottom of 1.8 oz shimeji mushrooms and separate them.
2. Discard the stems of 3 shiitake mushrooms and cut the caps into slices.
3. Discard the bottom of 3 cremini mushrooms and cut the caps into slices. Combine all the mushrooms on a plate/tray.
4. Roll up 6 shiso leaves (perilla/ooba) and cut them into julienned strips.
5. Open 1 (5-ounce) can albacore tuna (preferably packed in olive oil) and press the lid down to drain off the excess oil. Boil 4 QT (16 cups, 3.8 L) water in a large pot. Once boiling, add 1½ Tbsp salt.

To Cook

1. Cook 8 oz spaghetti 1 minute less than the package instructions (you will cook a bit more with the sauce). You should be able to finish the following step before the pasta is done cooking. If your pasta is done cooking first, reserve 4 Tbsp (60 ml) of pasta cooking water, drain, and set aside.
2. In a large frying pan, heat 1 Tbsp extra virgin olive oil on medium heat and add all of the mushrooms.
3. Sauté for 30–60 seconds to coat the mushrooms with oil, and then add the canned tuna.
4. Season with ⅛ tsp freshly ground black pepper and 1 tsp kobucha (kombucha) (or kosher salt).
5. Add 2 Tbsp sake, 2 Tbsp mentsuyu (concentrated noodle soup base), and 1 Tbsp unsalted butter and mix all together.
6. Reserve 4 Tbsp (¼ cup, 60 ml) of pasta cooking water and add to the pasta sauce.
7. Taste the sauce and adjust if needed. At this stage, the sauce should have a strong flavorful taste, not bland. If your pasta is not done cooking, turn off the heat and cover so the pasta sauce will not evaporate.
8. Drain the pasta into a colander OR scoop the pasta from the pot. Add the pasta to the sauce. Toss the sauce and pasta well.
9. Transfer the pasta to individual plates and garnish with 1 Tbsp shredded nori seaweed (kizami nori) and the shiso leaves.

To Store

1. You can keep the leftovers in an airtight container and store in the refrigerator for up to 2 days or in the freezer for a month.