Bring a large pot of salted water to a rolling boil. Add fettuccine noodles and cook according to package directions until al dente. Reserve 1 cup of pasta water before draining. Set the pasta aside.

While the pasta cooks, pat the shrimp dry with a paper towel. In a separate bowl, season the shrimp by tossing with 1 teaspoon garlic powder, 1 teaspoon onion powder, ½ teaspoon Italian seasoning, ½ teaspoon kosher salt, ½ teaspoon ground black pepper, and ½ teaspoon red pepper flakes (if desired).

Heat olive oil in a large skillet over medium-high heat. Add the seasoned shrimp in a single layer and cook for 1 - 2 minutes per side, until they turn pink and opaque. Do not overcook the shrimp, as they will become chewy if cooked too long. Remove from the skillet and set aside.

In the same skillet, melt ½ cup (1 stick) unsalted butter over medium-low heat. Add 3 cloves minced garlic (or garlic powder) and sauté for 1 minute until fragrant. Slowly pour in 2 cups of heavy cream while stirring continuously. Cook the mixture over medium-low heat for 4 - 5 minutes, ensuring it does not boil.

Gradually add 1½ cups grated Parmesan cheese to the sauce, stirring until fully melted. If the sauce is too thick, add some of the reserved pasta water, 1 tablespoon at a time, until you reach the desired consistency.

Add the cooked fettuccine noodles and tender shrimp to the skillet. Toss gently to coat everything evenly in the creamy Alfredo sauce. Cook for 3 - 5 minutes over medium heat until heated through.

Transfer the shrimp fettuccine Alfredo pasta to a serving dish. Garnish with fresh parsley and additional grated Parmesan cheese.

Serve immediately. Pair with garlic bread or a side salad for a complete meal. Enjoy!