Cook pasta according to package directions in salty water and drain, reserving 1 cup pasta water in a liquid measure for later.
Add frozen peas to a colander, and rinse under cold water until thawed, 1-2 minutes. Set aside.
In a large pot or dutch oven, heat olive oil over medium heat.
Add sliced scallions and garlic, season with salt, pepper and red pepper flakes, and cook 2-3 minutes, stirring to coat.
Add thawed frozen peas, heavy cream, and wine. Cook 10 minutes, stirring occasionally.
Blend with an immersion blender, or transfer to a blender and blend until smooth (it helps to cover the top of the blender with a towel when blending hot liquid). I like to reserve some whole peas for presentation and texture, or you could add additional peas at the end while serving.
Add the cooked pasta to pot with blended pea mixture, lemon juice, lemon zest, butter cubes, and cheese. Stir to coat, adding reserved pasta water as needed to reach desired consistency.
Taste, and add additional salt and pepper as needed.
Serve with additional grated parmesan and fresh basil leaves, if desired.