In a bowl, combine the room temperature butter with miso paste, soy sauce, rice vinegar, and sugar. Mix until roughly combined. It’s fine if the mixture is slightly chunky.
Boil your pasta one minute before al dente, then drain but do not rinse.
Immediately add the hot pasta to the miso butter mixture and toss until the sauce clings to every strand and forms a glossy coating.
Serve in a bowl and optionally top with chili crunch, black pepper, parmesan, and scallions.
