Salt the water well. Bring a large pot of water to a rolling boil and add enough salt so it tastes like the sea. This is your first layer of flavor.

Cook the spaghetti. Add the spaghetti and cook until just al dente, usually 1–2 minutes less than the package suggests. Before draining, scoop out 1–1.5 cups of starchy pasta water.

Build the garlic butter base. In a large skillet over medium heat, melt the butter with the olive oil. Add the garlic and a pinch of red pepper flakes. Cook 60–90 seconds, stirring, until fragrant but not browned.

Make it silky. Add a generous splash of reserved pasta water to the skillet and swirl. It should look glossy, not thin. Adjust heat to medium-low.

Toss the pasta. Add the drained spaghetti directly into the skillet. Toss for 1–2 minutes to coat every strand. If it looks dry, add more pasta water a little at a time.

Add cheese and herbs. Off the heat, shower in the Parmesan and toss until it melts into the sauce. Stir in most of the parsley (and basil or chives if using). Season with salt and black pepper. Add lemon zest and a squeeze of juice if you like a fresh lift.

Taste and adjust. If it needs more richness, add a small pat of butter. If it needs brightness, add more lemon or herbs. Finish with extra Parmesan and a drizzle of olive oil.

Serve right away. Twirl into bowls and sprinkle with the remaining herbs. Eat hot for the best texture.