Heat a large skillet over medium-high heat for about 2 minutes. Add the cleaned mushrooms without oil and sauté for about 5 minutes until browned and fragrant. Season with olive oil, salt, and pepper, then transfer to a bowl and set aside.

In a large pot, bring water to a boil, salt it generously. Add the dried bucatini and cook for about 8-10 minutes until al dente. Reserve about 2 cups of pasta water before draining.

In the same skillet, reduce heat to medium and melt 2 tablespoons of butter. Add minced garlic and sauté for about 30 seconds. Dissolve yellow miso paste in one cup of reserved pasta water, then stir into the skillet with sautéed mushrooms and heavy cream. Bring to a gentle boil and let simmer for 2 minutes.

Stir in grated pecorino Romano cheese until it melts into the sauce. Add cooked bucatini, tossing in the sauce while adjusting thickness with reserved pasta water as needed.

Plate the creamy Miso Mushroom Bucatini in bowls, garnishing with additional grated Parmesan cheese and finely chopped scallions. Enjoy!