Kosher salt and freshly ground black pepper
1 lb green beans, trimmed and cut into 2-inch lengths
1 lb short pasta
1/4 cup extra-virgin olive oil, plus additional for drizzling
4 cloves garlic, sliced
1/4 teaspoon crushed red pepper flakes
Zest and juice of 3 lemons
3 tablespoons unsalted butter
1/2 cup grated Pecorino-Romano, plus more for serving
1/2 cup chopped fresh parsley
½ lb shrimp peeled, deveined, and cut in half crosswise
Prepare a bowl of ice water and set it aside. Bring a large pot of salted water to a boil. Add the green beans and cook until bright green and just barely cooked through, 2 to 3 minutes. Use a spider or strainer to transfer the green beans to the ice bath and let cool completely before draining. Keep the water boiling in the pot.
Add the pasta to the same pot of boiling water. Let cook to al dente, about 3 minutes less than the package instructions. Save ½ cup pasta water. Drain the pasta.
Heat the olive oil in the pot over medium-high heat. Cook the garlic and red pepper flakes until fragrant but not browned, about 1 minute, then add the lemon zest, lemon juice, and pasta water.
Add the butter and shrimp. Stir for 2 minutes. Add drained pasta and blanched green beans, and cook, tossing, until well combined about 3 minutes more. Turn off the heat and gradually stir in the cheese, tossing constantly. Season with salt and freshly ground black pepper.
Divide pasta among serving bowls and garnish with parsley, more cheese, and a drizzle of olive oil.