In a large pot, heat the olive oil over medium-low heat. Add in the chicken, broccoli, and minced garlic. Cook until brown, about 7-10 minutes. Stir in creole seasoning and chili powder. Season with salt and pepper to taste.
Remove contents from pot and set aside, leaving any juices in the pot.
Add the butter and lemon juice. Once the butter is melted, whisk in the flour and cook for about 2 minutes until fully incorporated and the mixture becomes light brown.
Slowly whisk in the milk and continue to whisk until there are no lumps remaining.
Add in the pasta and cover the pot with a lid. Cook for 10 minutes, stirring occasionally, until thickened.
Remove the lid and let cook for about 5-7 minutes until the pasta is el dente.
Mix in the chicken, broccoli, nutmeg, parmesan cheese, and parsley until well combined.
Serve with a garnish of cheese.