01 -
Preheat an oven or air fryer to 400°F. Arrange French fries in a single layer on a rimmed baking sheet or in the air fryer basket. Bake or air fry according to package instructions or until golden and crispy.
02 -
In a 2-quart saucepan over medium heat, melt the butter. Whisk in the flour and cook for 2 minutes, until thick and pasty. Gradually whisk in the milk, about ½ cup at a time, stirring well to create a smooth sauce.
03 -
Add salt, pepper, ranch seasoning powder, and ¼ teaspoon cayenne powder. Stir to combine. Reduce heat to medium-low and cook for 5 minutes, stirring frequently, until the sauce thickens and clings to the back of a spoon.
04 -
Stir in the shredded white cheddar cheese with a silicone spoon. Cook for 2-3 minutes, stirring occasionally, until the sauce is thick and creamy. Remove from heat and set aside.
05 -
Transfer the cooked fries to a serving platter. Pour the Cajun ranch cheese sauce evenly over the fries. Sprinkle the remaining ¼ teaspoon cayenne powder on top. Serve immediately while warm.