Buttery Lemon Pasta With Almonds and Arugula

Preparation

1. Step 1

   Bring a large pot of heavily salted water to a boil. Add pasta and cook until it is 1 minute shy of being al dente, usually a minute or 2 less than the package instructions. Scoop out about 1½ cups pasta water, then drain pasta.

2. Step 2

   While the pasta cooks, in a large skillet or Dutch oven, melt butter over medium heat. Cook, swirling occasionally, until the foam subsides, the milk solids turn golden-brown and the butter smells nutty and toasty, 3 to 4 minutes. (Watch carefully to see that it doesn’t burn.)

3. Step 3

   Stir in almonds, rosemary and red-pepper flakes, and cook, stirring occasionally, until the nuts are toasted and slightly darker in color, about 1 minute.

4. Step 4

   Add about 1 cup pasta water to the skillet and bring to a simmer. Add lemon juice, zest, ½ teaspoon salt and a large pinch of black pepper, then add drained pasta and toss well. Add arugula, tossing until it wilts. Simmer for another minute, if needed, to thicken the sauce until it’s thick and glossy. If the mixture seems dry, add more pasta water 1 tablespoon at a time.

5. Step 5

   Taste and add more salt, red-pepper flakes and lemon juice, if needed. Serve topped with grated Parmesan and more red-pepper flakes, if you like.