Begin by bringing a large pot of water to a rolling boil. Add the elbow macaroni and cook for about 7 minutes, or until al dente—tender but still firm to the bite. Drain the pasta in a colander and set it aside while you prepare the flavorful sausage and creamy mixture.

In a large skillet, heat over medium-high heat, adding the diced Andouille sausage. Cook for about 5-7 minutes, stirring occasionally, until the sausage is caramelized and golden brown.

In a large mixing bowl, combine the drained macaroni with the caramelized sausage, cheddar cheese soup, both types of grated cheese, sour cream, onion powder, Cajun seasoning, and black pepper. Mix everything thoroughly until well combined.

Lightly grease your slow cooker with cooking spray or oil. Carefully transfer the macaroni and cheese mixture into the slow cooker, spreading it evenly to ensure even cooking.

Cover the slow cooker with its lid and set it to low heat. Allow it to cook for 3 hours, stirring occasionally if possible.

Once your Slow Cooker Cajun Mac and Cheese is ready, give it a gentle stir to incorporate any layers that may have formed. Serve hot and enjoy!