Use starchy potatoes like Russet or Yukon Gold
Cut potatoes into evenly sized pieces
Rinse or soak cut potatoes to remove excess starch
Dry potatoes thoroughly before cooking
Parboil potatoes until just tender
Drain and let potatoes steam-dry
Rough up the edges slightly after parboiling
Use a large skillet or sheet pan with plenty of space
Heat oil or fat until hot before adding potatoes
Do not overcrowd the pan
Cook over medium-high to high heat
Let potatoes sit undisturbed to form a crust
Turn only after one side is deeply browned
Add salt near the end of cooking
Finish with butter only after crisping is done
Use a cast-iron skillet for better browning
Roast in a hot oven if making a larger batch
Serve immediately for best crispiness