Bring a large pot of salted water to a boil. Add pappardelle and cook al dente according to package instructions.
Reserve ½ cup pasta water, then drain. Tip: Saving pasta water helps loosen the sauce if it’s too thick later.
Saute Garlic
In a medium saucepan, heat olive oil over medium heat. Add minced garlic and cook 1–2 minutes until fragrant. Tip: Don’t brown the garlic; it will turn bitter.
Add the Cream
Pour in heavy cream and bring to a gentle simmer over medium-low heat. Stir occasionally to prevent sticking.
Add the Basil
Tear or roughly chop fresh basil leaves and stir into the cream. Let them wilt for 1–2 minutes. Tip: Fresh basil gives a bright flavor, so add it just before blending.
Blend the Sauce
Remove the pan from heat and carefully transfer to a blender or use an immersion blender to puree until smooth. Tip: Blending hot cream can be tricky—hold the lid with a towel and start slowly.
Finish Sauce
Return the sauce to low heat. Stir in grated Parmesan and butter until melted and fully incorporated. Tip: If the sauce is too thick, add a splash of reserved pasta water to reach your desired consistency.
Season
Taste and add salt and pepper as needed.
Combine with Pasta
Add the drained pasta to the sauce and toss to coat evenly. Tip: Tossing in the pan over low heat helps the sauce cling to the noodles.
Serve Immediately
Garnish with extra Parmesan or basil leaves if desired.