Bring a large pot of salted water to a boil. Add pasta and cook according to package directions until al dente, about 8-10 minutes. Reserve 1/2 cup of pasta water before draining.

In a large skillet, heat olive oil over medium-high heat. Add shrimp seasoned with salt, black pepper, and red pepper flakes. Cook for 1-2 minutes on each side until shrimp turn pink.

In the same skillet, add asparagus and sauté for 3-4 minutes until bright green and tender-crisp.

Return cooked shrimp to skillet, add drained pasta, and toss together. Stir in basil pesto and enough reserved pasta water to create a creamy sauce.

Serve hot, topped with grated Parmesan cheese and lemon zest, if desired.