1. Bring a large pot of generously salted water to a boil. Cook the fettuccine according to package directions until al dente. Before draining, scoop out ½ cup of the starchy pasta cooking water and set it aside. Drain the pasta.

2. Heat olive oil in a large skillet over medium heat. Add the garlic and cook for 1 minute until fragrant. Add the baby spinach in batches, stirring between additions, and cook for 2–3 minutes until completely wilted.

3. Transfer the wilted spinach and garlic to a blender. Add the heavy cream and ¼ cup of the reserved pasta water. Blend until completely smooth and vibrantly green. Pour the sauce back into the skillet over low heat and stir in the Parmesan until melted and fully incorporated.

4. Bring a small pot of salted water to a boil. Add the asparagus pieces and cook for 2 minutes. Add the frozen peas and cook for 1 more minute. Drain immediately and rinse under cold water to stop the cooking and preserve the vivid green color.

5. Add the cooked fettuccine, blanched asparagus, and peas to the skillet with the spinach sauce. Toss everything over medium-low heat, adding the remaining pasta water a splash at a time until the sauce coats every strand. Stir in lemon zest and lemon juice, season with salt and pepper, and serve immediately topped with extra Parmesan and fresh herbs.