In a skillet over medium heat, cook the diced andouille sausage until browned and crispy. Remove with a slotted spoon and set aside.,Add butter to the skillet with the rendered sausage fat. Once melted, add the chopped onion and cook until softened, about 3–4 minutes.,Stir in the minced garlic and cook for 30 seconds until fragrant.,Sprinkle the flour over the onion mixture and whisk constantly for 1–2 minutes to form a roux.,Slowly whisk in the milk and chicken broth, stirring until smooth.,Add the Cajun seasoning and smoked paprika. Stir to combine.,Bring the gravy to a simmer, then reduce heat and cook for 5–7 minutes until thickened.,Return the sausage to the pan and stir to combine. Season with salt and pepper to taste.,Serve hot over biscuits, grits, or your favorite Southern dish. Garnish with chopped parsley if desired.