In a large pot, bring 4 quarts of water to a boil. Add 1 tablespoon of salt to the boiling water. This enhances the flavor of the pasta.

Add 12 oz of spaghetti to the boiling water and cook according to package instructions until al dente, usually about 8-10 minutes.

Once cooked, reserve 1 cup of pasta water, then drain the pasta in a colander and set aside.

In a large skillet, heat 1 tablespoon of olive oil over medium-high heat. This helps to sear the shrimp quickly.

Season the shrimp with 1 teaspoon of salt and 1/2 teaspoon of black pepper. Add the shrimp to the skillet in a single layer.

Cook the shrimp for about 2-3 minutes on each side until they are pink and opaque. Remove from the skillet and set aside.

In the same skillet, reduce the heat to medium and add 1/2 cup of unsalted butter. Allow it to melt slowly.

Add 6 minced garlic cloves to the melted butter. Sauté for about 1-2 minutes until fragrant, but be careful not to burn the garlic as it can turn bitter.

If using, add 1/4 teaspoon of red pepper flakes for a little heat. Stir to combine.

Add the cooked pasta to the skillet with the garlic butter sauce. Toss to coat the pasta evenly.

If the pasta seems dry, add reserved pasta water a little at a time until desired consistency is reached.

Return the cooked shrimp to the skillet and toss everything together until well combined.

Remove from heat and stir in chopped parsley for freshness.

Serve immediately, garnished with grated Parmesan cheese.