Cook biscuits according to package directions.
Brown ground sausage until half cooked through, then add salt, pepper, and cajun seasoning.
Continue cooking the sausage through, DO NOT DRAIN!
Add the flour and stir until fully incorporated and all of the grease has been soaked up.
Add milk, and cook on med-low heat until bubbly and thickened.
(Optional) Add 2TB of milk at a time to thin gravy, if needed.
Serve over warm biscuits.