Creamy Bucatini With Spring Onions and Mint

Preparation

1. Step 1

   Bring a large pot of heavily salted water to a boil over high heat. Add pasta and cook until it is just shy of al dente, usually 2 minutes less than the package instructions. Reserve about 1 cup pasta water for the sauce (a coffee mug is good for this), then drain the pasta.

2. Step 2

   Meanwhile, in a large skillet, melt butter over medium-high heat. Add onions and cook, stirring occasionally, until golden brown at the edges and thoroughly soft, 12 to 15 minutes.

3. Step 3

   Add heavy cream, rosemary, ½ teaspoon salt, red-pepper flakes, and a few grinds black pepper to the pan, and bring to a simmer. Let cream reduce and thicken, 2 to 4 minutes.

4. Step 4

   Reduce heat to low and stir in Pecorino Romano until combined. Add the drained pasta and about ½ cup of the reserved pasta water. Toss well to coat the pasta. If the sauce is too thick, add pasta water by the tablespoon; if it’s too thin, let it bubble and reduce for a minute or so. Remove from heat and stir in lemon zest and chives. Taste and add more salt, if needed.

5. Step 5

   Serve in bowls, each topped with more chives, mint, a generous amount of black pepper and a sprinkle of pistachios.