Bring a large pot of salted water to a boil. Cook spaghetti until al dente, about 8-10 minutes. Reserve 1 cup of pasta water, then drain.

In a large skillet, heat olive oil over medium heat. Add minced garlic and sauté until golden, releasing a nutty aroma, about 1-2 minutes.

Add red pepper flakes to the skillet, stirring for another 30 seconds until fragrant. Be careful not to burn the garlic.

Remove the skillet from heat and stir in lemon juice and zest. The aroma should be fresh and citrusy.

Return drained pasta to the skillet, adding reserved pasta water gradually. Toss to coat the pasta evenly with the sauce.

Stir in grated Parmesan cheese, allowing it to melt and thicken the sauce slightly. The cheese should create a creamy texture.

Season with salt and black pepper to taste. Adjust the consistency with more pasta water if needed.

Garnish with chopped parsley and serve immediately, enjoying the contrast of creamy sauce and al dente pasta.