Begin by cooking the pasta. Bring a large pot of salted water to a boil. Add the fettuccine and cook according to package instructions until al dente. Drain and set aside.
In a large skillet, heat 2 tablespoons of butter over medium heat. Once melted, add the minced garlic and sauté for about 1 minute until fragrant.
Add the bite-sized steak pieces to the skillet. Season with salt and black pepper. Sear the steak for about 3-4 minutes on each side until they reach desired doneness. Remove the steak from the skillet and set aside.
In the same skillet, lower the heat and add the remaining 2 tablespoons of butter along with the heavy cream. Stir well, scraping up any browned bits from the bottom of the pan.
Add the garlic powder, salt, black pepper, and Parmesan cheese to the creamy sauce. Stir until smooth and thickened.
Toss the drained pasta in the creamy Parmesan sauce until fully coated. If necessary, add a little pasta water to adjust the consistency.
Add the garlic butter steak bites back into the skillet with the pasta and mix gently to combine. Cook for an additional minute to heat through.
Serve hot, garnished with fresh parsley if desired.