They are prepared by cutting potatoes into even strips, drying them, and frying them, usually in a deep fryer. Pre-cut, blanched, and frozen russet potatoes are widely used, and sometimes baked in a regular or convection oven; air fryers are small convection ovens marketed for frying potatoes.A quality french fry cutter makes it easy to slice through potatoes and create delicious, uniformly sized french friest's said that this dish was discovered by American soldiers in Belgium during World War I and, since the dominant language of southern Belgium is French, they dubbed the tasty potatoes “French” fries.