Heat the olive oil for the sauce in a medium saucepan and sauté the onions for 1 to 2 minutes. Drain maitake and reserve soaking water. Add all remaining ingredients except the shoyu and pasta. Cover, bring almost to a boil, reduce the heat to medium-low ,and simmer for about 30 to 35 minutes. Add the shoyu and simmer another 5 minutes.
While the sauce is cooking, cook the pasta as package directs. When done, remove, drain and serve with sauce.
7g fat (19% calories from fat),