01 - Preheat oven to 425°F.
02 - If using fresh potatoes, soak cut fries in cold water for 30 minutes, then drain and pat dry.
03 - Toss fries with vegetable oil and spread on a baking sheet in a single layer. Bake for 25-30 minutes, turning halfway, until golden and crispy. If using frozen fries, bake according to package instructions.
04 - Cook turkey bacon in a skillet over medium heat for 5-7 minutes until crisp. Transfer to a paper towel-lined plate and let cool, then crumble into bits.
05 - Once fries are cooked, transfer to an oven-safe serving dish. Sprinkle evenly with cheddar and mozzarella cheese.
06 - Return fries to the oven for 3-5 minutes, or until cheese is fully melted and bubbly.
07 - Remove from oven, top generously with turkey bacon bits, and sprinkle with chives or green onions if using.
08 - Serve immediately, with sour cream on the side if desired.