Add the cubed steak to a medium bowl. Pour the buttermilk and Worcestershire sauce over the top. Give it a stir, making sure the steak is completely submerged in the buttermilk. Set aside or refrigerate until ready to fry.
Heat about ½ inch of oil over medium-high heat in a heavy cast iron skillet.
In a bowl or large pie plate, mix together flour, salt, pepper, garlic powder, and cayenne. You may also need more flour, so adjust as needed.
Remove one piece of steak at a time, shake off excess buttermilk, and dredge in the flour mixture, coating both sides.
Carefully place the prepared steak in the hot oil. Cook for 3 to 4 minutes on one side. Flip to the second side and cook for an additional 2 to 3 minutes until browned.
Remove steaks to a paper towel lined plate and keep warm until serving.
Notes
Tips for the Best Fried Cube Steak
Use a Heavy Skillet: A heavy-bottom skillet will work if you don't have a cast-iron skillet.
Don't Skip the Soak: Letting the cube steak marinate in buttermilk helps tenderize the meat and adds excellent flavor. Even if you only have 10 minutes, this helps tremendously.
Check Your Oil Temperature: Make sure the oil is hot enough before frying—heat it over medium-high until a pinch of flour sizzles when dropped into the oil. If the oil isn't hot enough, the coating will absorb too much grease and turn out soggy instead of crispy.
Fry in Batches: Fry in batches so the steaks cook evenly and stay crispy.