Make the Cajun seasoning. Mix all the ingredients for the Cajun seasoning in a small bowl. If you’re short on time, you can substitute ¼ cup of store-bought Cajun seasoning.
Coat the wings. Pat the wings dry with paper towels to remove excess moisture. Then, combine the flour and 1 tablespoon of Cajun seasoning in a large ziplock bag. Add the wings to the bag, seal them, and shake until they are evenly coated.
Heat the oil. Heat peanut oil in a deep fryer or heavy pot to 370°F (190°C). Make sure the oil is hot enough to give the wings a crispy exterior without absorbing too much oil.
Fry the wings. Fry the wings in batches, making sure they aren’t overcrowded. Cook for 12 minutes until the wings are golden brown and cooked through (internal temperature should reach 165°F or 75°C). Then, remove the wings from the oil and place them on a paper towel-lined plate to drain excess oil.
Make the Cajun butter sauce. In a saucepan over medium-low heat, melt the butter. Stir in 3 tablespoons of the Cajun seasoning until fully combined and fragrant.
Toss and serve. Place the fried wings in a large bowl, pour the Cajun butter sauce over them, and toss until they are well coated. Serve immediately with ranch or blue cheese dressing on the side.