Bring a large pot of salted water to a rolling boil. Add the fettuccine and cook until al dente according to package directions. Reserve 1/2 cup of the pasta cooking water before draining. Drain and set aside.

Heat olive oil in a large skillet over medium heat. Add minced garlic and sauté for about 1 minute until fragrant but not browned.

Add chopped spinach and cook, stirring, until wilted, about 2 to 3 minutes. Remove from heat.

Transfer the garlic and spinach mixture to a blender. Add heavy cream, Parmesan, salt, black pepper, nutmeg (if using), and lemon juice. Blend until smooth and velvety.

Return the sauce to the skillet and warm gently over low heat. Thin with reserved pasta water as needed.

In a separate pot, bring water to a boil and blanch the asparagus for 2 minutes. Add the peas and cook for an additional minute. Drain and add the vegetables to the sauce in the skillet.

Add the cooked fettuccine to the skillet and toss gently to coat the pasta in the sauce. Use more reserved pasta water if necessary.

Finish with chopped basil, toasted pine nuts or almonds, and extra cheese or lemon zest if desired. Serve immediately.