In a large pot of salted boiling water, cook the pasta according to the package instructions until al dente. Drain the pasta, reserving 1/2 cup of pasta water for later. Set aside.
- While the pasta is cooking, heat olive oil in a large skillet over medium heat. Add the asparagus and cook for 4-5 minutes until tender but still crisp. Season with a pinch of salt and pepper. Remove the asparagus from the skillet and set aside.
- In the same skillet, add the minced garlic and cook for about 1 minute until fragrant. Add the heavy cream and bring to a simmer. Stir in the parmesan cheese and cook until the sauce thickens slightly, about 2-3 minutes. If the sauce becomes too thick, add some of the reserved pasta water, a little at a time, until the desired consistency is reached.
- Add the cooked pasta to the skillet and toss to coat in the creamy sauce. Stir in the cooked asparagus, red pepper flakes (if using), and adjust the seasoning with salt and pepper as needed.
- Serve the creamy asparagus pasta immediately, garnished with fresh lemon zest and herbs if desired.