1 tablespoon soy sauce (regular shoyu, try to use marudaizu (whole soy bean) if you can find it)
3 Tablespoons unsalted butter
chives for garnish can also use shiso (nori or green onion)
Instructions
Prepare a boiling pot of salted water and cook fresh spaghetti until barely al dente and set aside
Prepare the mentaiko sauce by removing the eggs with a spoon from the egg sack. Combine with milk, soy sauce, mayo in a small bowl or cup and set aside.
Once the pasta has cooked, drain and reserve 1/4 cup pasta water.
Using a large skillet or clean pot, on medium heat, melt the butter and add the pasta. Toss until pasta is evenly coated, roughly 20-30 seconds and turn heat to low.
Add in the mentaiko sauce, mix to evenly coat noodles another 20-30 seconds. Be careful not to allow all the liquid to evaporate. If you did, add in reserved pasta water to thin.