Bring a large pot of salted water to a rolling boil. Add the spaghetti and cook until al dente, about 8–10 minutes. Reserve ½ cup of pasta water, drain the pasta, and toss with a drizzle of olive oil.

In a skillet over medium-low heat, melt the butter with olive oil. Add the minced garlic and sauté for 1–2 minutes until fragrant.

Sprinkle in the Italian seasoning and lemon zest, toasting together for about 30 seconds.

Pour in the lemon juice and let it simmer for 1–2 minutes to meld flavors.

Add the cooked pasta to the skillet, tossing with the sauce and gradually adding reserved pasta water.

Fold in the chopped parsley and season with salt and pepper to taste.

Serve topped with grated Parmesan and crushed red pepper flakes, if desired.