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 2 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.