Preheat your oven to 450 F. Line a large baking sheet with foil or use a silpat.
Add the fries and arrange them into one layer. Bake for 15 minutes.
Sprinkle the fries with half of the Cajun seasoning and flip. Return to the oven and bake another 10-15 minutes or until golden brown with crispy edges.
Sprinkle tops of fries with the cheese, remaining Cajun seasoning, and the bacon. Return to the oven and bake another 5 minutes to melt the cheese.
Sprinkle with green onion and serve with Ranch dressing.