Fry the beef katsu. In a pan that is at least 2.5 inches deep, fill with vegetable oil until 1 inch full, and heat over medium heat. When oil is heated to 350ºF, carefully add the cutlet to the pan.
Fry for 1-2 minutes, flip cutlet, and fry for an additional 2-3 minutes or until golden brown. Repeat step to fry the remaining cutlets. Drain oil and set aside.