If You’re Making Miso Butter Pasta, a Few Tips

• Cook the pasta less than the package instructions. Because the pasta gets finished in the sauce, you’ll want to keep that great al dente texture. Plan to cook for one minute less than the instructions call for al dente. 
• Reserve some pasta water. This is the key ingredient for making a lush, glossy sauce. You’ll use between 1 and 1 1/2 cups, but it never hurts to have a little more just in case.
• Add miso to the pasta water. Rather than whisk the miso paste directly into the butter in the pan (it’s tough to get all those little lumps out), first combine it with one cup of the pasta water and whisk together. It easily softens and dissolves into the water and the sauce stays lump-free.
• Add more water as needed. If at any point the sauce feels too thick, add more pasta water to the skillet a few tablespoons at a time. I think an additional 1/2 cup makes for an ample amount of sauce with a nice consistency. 
• The panko topping is optional. A sprinkle of toasted panko breadcrumbs over the pasta adds a really nice contrast. But it might not be for all eaters, and that’s OK. The dish will still be totally delicious, even if you skip it.

Ingredients

• 8 Tablespoons (1 stick) unsalted butter, divided
• 1/2 cup panko breadcrumbs
• 1/4 teaspoon kosher salt, plus more for the pasta water
• 1/8 teaspoon red pepper flakes (optional)
• 1 ounce Parmesan cheese (1/2 cup firmly packed freshly grated or 1/3 cup store-bought grated)
• 1 clove garlic
• 1 pound long dried pasta, preferably mafaldine, bucatini, or linguine
• 1/4 teaspoon freshly ground black pepper
• 1/4 cup white or yellow miso paste

Procedure

1. Bring a large pot of salted water to a boil.
2. Meanwhile, melt 2 Tablespoons of the unsalted butter in a large, high-sided skillet over medium heat. Add 1/2 cup panko breadcrumbs, 1/4 teaspoon kosher salt, and 1/8 teaspoon red pepper flakes if using. Cook, stirring regularly, until golden brown, about 3 minutes. Transfer to a small bowl and wipe the skillet clean with paper towels.
3. Finely grate 1 ounce Parmesan cheese (about 1/2 packed cup) or measure out 1/3 cup store-bought grated, plus more for serving, if desired. Finely grate 1 garlic clove.
4. Add 1 pound long dried pasta to the boiling water and cook for 1 minute less than the package instructions for al dente.
5. Reserve 1 1/2 cups of the pasta water. Drain the pasta.
6. Place 1/4 cup white or yellow miso paste and 1 cup of the pasta water in a glass measuring cup or small bowl. Whisk until smooth.
7. Melt the remaining 6 tablespoons unsalted butter in the reserved skillet over medium heat.
8. Add the garlic and cook until fragrant, 20 to 30 seconds.
9. Add the miso mixture and 1/4 teaspoon black pepper. Whisk until mostly smooth. Bring to a simmer. Cook, stirring regularly, until slightly thickened, 1 to 2 minutes.
10. Add the Parmesan cheese and whisk to combine.
11. Add the pasta and toss to coat. If the sauce is too thick, thin it out with more pasta water a tablespoon at a time.
12. Serve topped with the breadcrumbs. Taste and season with more kosher salt and black pepper as needed.

Cook’s Notes

Storage: Leftovers can be refrigerated in an airtight container for up to 4 days. Reheat over low heat on the stovetop and thin the sauce out with a few spoonfuls of water.