Preheat the oven to 400°F
Spread the fries in a single layer on a baking sheet
Bake for 5 to 10 minutes, flipping once halfway through
Heat an air fryer to 375°F
Place the fries in the basket in a single layer
Air fry for 3 to 5 minutes, shaking once halfway through
Heat a skillet over medium heat
Add a small amount of oil
Cook the fries for 3 to 5 minutes, turning occasionally
Use a microwave only if needed
Place the fries on a microwave-safe plate with a paper towel
Heat in short 20 to 30 second intervals
Serve immediately after reheating