Take out a blender or a food processor to prepare the alfredo sauce. Add all of the ingredients for the sauce and blend them on high until it's completely smooth and creamy, scraping down the sides as needed. Set it aside for now.
Take out a cutting board and a knife. Pat your chicken breast(s) dry and cut them into about 1 inch pieces.
Season your diced chicken with garlic powder, smoked paprika, salt and black pepper. Mix everything together and set it aside for now.
Turn a burner on high heat and bring a large pot of salted water to a boil.
Add your dry pasta and cook it according to the package directions until al dente. Before draining the pasta, reserve about 1 cup of the starchy pasta water. Drain the pasta and set it aside for now.
Reduce the heat down to medium and place a large nonstick skillet on top of it. Give it a light spray of oil.
Add your seasoned chicken in a single layer. Cook it on medium heat for 3-4 minutes to let it sear on the outside. Then add your broccoli and let it cook for 5 to 8 minutes until fully cooked.
Turn the heat down to low, then add your cooked pasta into the large skillet. Use a larger pot if necessary.
Pour your blended sauce over everything and mix well.
Stir it continuously as it warms up. It will thicken as it heats. Add about 1/4 to 1/2 cup of the reserved pasta water and then turn the heat off once it's hot and creamy.
Taste it and add more salt, pepper, or a squeeze of lemon if needed. Garnish it with fresh parsley and red chili flakes (if using) and serve it right away.
