Cook the Pasta: Bring a large pot of salted water to a rolling boil. Add your spaghetti and cook according to the package directions until al dente. In the final 3 minutes of cooking, toss in the broccoli florets. Once done, drain the pasta and broccoli, but make sure to reserve 1/2 cup of the starchy pasta water for later use.
Sauté Garlic: In a spacious skillet, pour in the olive oil and heat over medium flame. Add the minced garlic and optional red pepper flakes, sautéing them for 1-2 minutes until the garlic turns fragrant and golden—be careful not to let it burn.
Combine Ingredients: Add the drained pasta and broccoli to the skillet, carefully tossing them with the garlic oil. Incorporate the lemon zest and lemon juice, mixing thoroughly. If the pasta seems dry, gradually add some reserved pasta water until you reach a velvety texture.
Season: Generously season the mixture with salt and freshly cracked black pepper according to your taste. Toss everything for about a minute to ensure the flavors are well blended and fragrant.
Serve: Transfer the pasta to serving plates. If desired, sprinkle with grated Parmesan cheese and finish with a few fresh basil leaves for that vibrant touch.
Notes
Serve in a large bowl with a lemon wedge and extra basil for presentation.