Bring a large pot of salted water to a boil. Add the spaghetti and cook according to package instructions until al dente, usually about 8-10 minutes. Stir occasionally to prevent sticking.

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

In a large skillet, heat 1 tablespoon of olive oil over medium-high heat. Add the shrimp, season with salt and pepper, and sauté for about 2-3 minutes on each side until they turn pink and opaque.

Remove the shrimp from the skillet and set aside on a plate.

In the same skillet, reduce the heat to medium and add 4 tablespoons of butter. Once melted, add the minced garlic and sauté for about 1-2 minutes until fragrant, being careful not to burn the garlic.

Pour in the white wine (or chicken broth) and let it simmer for about 2-3 minutes, allowing the alcohol to cook off and the sauce to reduce slightly.

Add the cooked shrimp back into the skillet along with the drained spaghetti. Toss everything together, adding reserved pasta water a little at a time until you reach your desired sauce consistency.

Stir in the remaining 2 tablespoons of butter until melted and well combined. Adjust seasoning with more salt and pepper if needed.

Serve immediately, garnished with chopped parsley and grated Parmesan cheese.