Bring a large pot of salted water to a boil
Cook both types of fettuccine together according to package directions until al dente
Reserve ½ cup of pasta water, then drain the pasta
In a large skillet, melt butter over medium heat
Add minced garlic and cook until fragrant (about 1 minute)
Stir in the heavy cream and warm it gently, allowing it to thicken slightly
Stir the peas into the cream sauce, then sprinkle in the Parmesan cheese. Stir until the sauce is creamy and smooth (If the sauce gets too thick, loosen it with a splash of reserved pasta water)
Toss the cooked pasta into the sauce, stirring gently to coat every strand.
Season with salt and black pepper to taste. (Optional: Stir in diced prosciutto or ham if you want a heartier version)
Plate immediately and sprinkle with extra Parmesan if you like. Best enjoyed fresh and warm!