Place rack in top third of oven, add sheet pan + preheat oven to 475°; peel (or don't peel!) 2 potatoes, cut into ½-inch sticks, mix with 2 tbsp oil + salt/pep; carefully remove hot pan from oven, spread fries onto pan + bake 25 min; flip fries over, reduce heat to 425° + bake 10 min more until golden; remove fries from oven + lower oven temp to 400°

Meanwhile, cut 2 onions in half from root to stem, peel + thinly slice; heat 1 tbsp oil in skillet over med + cook onions 20-25 min, stirring occasionally until browned + caramelized (do not allow onions to burn)

Line a sheet pan with foil, add cooked fries then top with caramelized onions + layer with 4 slices of cheese; bake fries 5-7 min until cheese is melty; drizzle with ¼ cup sauce