Step 1

Put half the mushrooms in a food processor and pulse until roughly minced. Chop the remaining mushrooms into 1/4-inch pieces.

Step 2

Heat oil in a large heavy pot over medium heat. Add onion; cook, stirring frequently, until translucent. Add carrots and celery; cook, stirring, until softened, 3 to 4 minutes. Add the minced and chopped mushrooms and salt; cook, stirring, until the mushrooms start to release their juices. Add oat milk; cook, stirring, until it evaporates. Stir in nutmeg. Add wine; cook, stirring, until it evaporates. Add tomatoes and bring to a boil.

Step 3

Lower the heat to maintain a low simmer; cook for 45 minutes, stirring occasionally. (If the sauce looks dry, add boiling water, 1/4 cup at a time.)

Step 4

Meanwhile, bring a large pot of water to a boil. Cook pasta according to package directions; drain. Serve the pasta topped with the sauce and garnished with Parmesan, if desired.