Bring a large pot of salted water to a boil, cook the fettuccine until al dente according to package instructions, reserve ½ cup pasta water, drain the pasta, then set aside.
Heat olive oil in a large skillet over medium-high heat, season the chicken strips with garlic powder, Italian seasoning, salt, and black pepper, cook for 5–6 minutes until golden brown and fully cooked through at 165°F, remove from skillet, then set aside.
Using the same skillet, melt butter over medium heat, add minced garlic, sauté for 1 minute until fragrant, optionally add sun-dried tomatoes and cook for 30–60 seconds to infuse more flavor.
Pour in heavy cream, let it gently simmer for 3–4 minutes, reduce heat to low, whisk in freshly grated Parmesan cheese until smooth and creamy, season with salt, black pepper, and nutmeg, add reserved pasta water if needed to thin the sauce.
Add the cooked chicken back into the skillet, add drained fettuccine, add chopped sun-dried tomatoes, toss gently until evenly coated in the Alfredo sauce, simmer for 1–2 minutes so the pasta absorbs the creamy sauce.
Plate immediately, garnish with extra Parmesan cheese, chopped parsley, optional cracked black pepper, or red pepper flakes, then serve warm.