Cook the french fries according to the package directions. For the crispiest results, use an air fryer or deep fryer.

While the fries cook, prepare the cheese sauce. Melt the butter in a medium saucepan over medium heat. Whisk in the flour and cook for 1 minute to form a roux.

Slowly whisk in the cold milk, stirring continuously to prevent lumps. Cook for 3-5 minutes until the mixture thickens and coats the back of a spoon.

Remove the saucepan from the heat. Gradually stir in the freshly grated cheddar cheese until completely melted and smooth. Season with salt.

Assemble the dish: Spread the hot, crispy fries onto a serving platter or parchment-lined basket.

Generously pour the hot cheese sauce all over the fries.

Drizzle the ranch dressing evenly over the cheese-covered fries.

Liberally dust the fries with Cajun seasoning to reach your desired spice level.

Garnish with finely chopped fresh parsley and serve immediately while hot and crispy.