Scrub and clean well the potatoes after which grate them on a large-holed cheese grater.
Arrange the potatoes on a fine-mesh sieve, cover, and rinse under cold water until the water runs clear.
Drain the potatoes very well after which place them on a clean tea towel, press another towel onto them to remove any remaining moisture. Removing as much moisture as possible is key.
Transfer the potatoes to a large bowl and toss with the salt, garlic powder, onion powder, paprika and also some black pepper if desired.
Place a large cast iron skillet over medium heat and once warm add the oil, heat it until it starts shimmering and if you add a piece of grated potato sizzles on contact.
Add the grated potatoes to the hot oil in ONE LAYER, press them down slightly and fry undisturbed for about 2 minutes to get them crispy and golden-brown.
Stir, press and cook for another 2 minutes. Repeat as needed until the potatoes are crispy and golden brown, about 6 - 8 more minutes.
Transfer the cooked hash browns to a paper towel-lined plate and let them drain of excess oil. In the meantime, cook the remaining potatoes.
Serve hot with a runny egg on top.