Wash and scrub potatoes. Using a box grater or a food processor, shred the potatoes. (If you prefer, you can peel the potatoes before shredding them.)
Place shredded potatoes into a cold water bath. Stir the potatoes until the water becomes cloudy. Drain the water and repeat.
Spread the potatoes out into a single layer on a kitchen towel or layered paper towels. Pat the potatoes dry. Then wrap the towel around the potatoes and squeeze to remove any excess moisture. (Be careful if using paper towels, you don't want them to break open.)
Place a large skillet over medium heat. Melt half the butter in your skillet. Once butter is melted and the skillet is hot, add potatoes spreading them into a single layer. Season with half of the salt, pepper, and cayenne pepper.
Cook the potatoes for 5 minutes until a brown crust forms on the bottom. Flip the potatoes and cook for another 5 minutes. (I flip the potatoes in sections instead of trying to flip the whole thing at once.)
Once the potatoes are browned and crispy, portion hash browns on everyone's plates and serve immediately. Repeat with remaining ingredients.
Notes
If you like your potatoes extra crispy, you can cook each side once more for 3 minutes per side, or until they're cooked to your desired crispiness level.