Using a conventional blender will produce the smoothest sauce, but an immersion blender can be used if needed. We prefer the richness of whole-milk yogurt, but low-fat yogurt can be used instead. There is no need to peel the broccoli stalks here.

Bring 4 quarts water to boil in large pot. While water is coming to boil, heat 1 tablespoon oil in 10-inch skillet over medium heat until shimmering. Add panko and cook, stirring frequently, until golden brown, about 4 minutes. Off heat, stir in ⅛ teaspoon salt and ⅛ teaspoon pepper. Transfer panko to plate to cool.

Add broccoli stalks, garlic, and 1 tablespoon salt to boiling water and cook, stirring occasionally, until stalks are tender, about 6 minutes. Using spider skimmer or slotted spoon, transfer stalks and garlic to blender; set aside.

Return water to boil. Add florets and cook until bright green and tender, about 3 minutes. Using spider skimmer, transfer two-thirds of florets to bowl. Transfer remaining florets to blender with stalks and garlic. Return water to boil, add pasta, and cook, stirring often, until al dente.

While pasta cooks, add basil; yogurt; Pecorino; pine nuts; lemon zest and juice; anchovies, if using; and remaining ½ cup oil, 2 teaspoons salt, and 1 teaspoon pepper to blender and process until mixture resembles pesto, about 20 seconds, scraping down sides of blender jar. With blender running, slowly add ½ cup water and process until sauce is smooth and thick but fluid, about 20 seconds, adding additional water as needed.

Reserve 1 cup cooking water, then drain pasta and return it to pot. Off heat, add sauce and reserved florets and stir gently to combine. Adjust consistency with reserved cooking water as needed. Season with salt to taste, and serve immediately, passing panko and extra Pecorino separately.

Blanching Makes Broccoli Greener