1cupfreshly grated parmesan cheeseoptional, not authentic
Instructions
Bring a large pot of water to a boil and add 3 tablespoon kosher salt. Stir in the pasta and cook according to the package directions.
While the pasta is cooking, heat the olive oil in a large skillet over medium heat. Add the crushed red pepper flakes and garlic to the pan. Cook until the garlic begins to turn golden (do not overcook, the garlic will become bitter if cooked too long, if this happens, start over.) Turn off the heat and stir in the butter.
Drain the pasta and reserve 1 cup of the cooking water. Add the pasta to the skillet and toss to coat. Turn the heat to medium-high. Add ½ cup pasta water, then 1–2 Tbsp at a time until the desired consistency. Bring the mixture to a boil.
Turn the heat to low and add the salt. Cook until the mixture is reduced by 1/2. Turn off the heat.
Toss the pasta with the parsley and cheese. Serve immediately.
Video
Notes
Salt like a pro: Season the pot (about 1 Tbsp kosher salt per 4 qts water) so the pasta is flavorful before it hits the pan.
Heat level: Use ¼-½ tsp crushed red pepper to taste; bloom it briefly with the garlic for aroma.
Cheese & butter (optional, non-traditional): Add off heat and toss in gradually so the emulsion stays smooth.
Bright finish: A squeeze of lemon and a handful of parsley at the end wake everything up.
Variations: Melt 2 anchovy fillets with the garlic for umami, or top with pangrattato (toasted breadcrumbs) for crunch.
Make ahead: Slice garlic up to 1 day ahead; keep covered and chilled in oil. Cook pasta fresh for best texture.
Storage & reheat: Refrigerate up to 3 days. Reheat gently in a skillet with a splash of water to re-emulsify; add a touch of oil if needed.
Gluten-free: Use your favorite gluten-free spaghetti and reserve extra pasta water, you may need a bit more to get the same sheen.