Scrub the potatoes clean and grate them on a large-holed cheese grater (I left the skin on, but you can peel it first if you’d like). In a fine-mesh sieve, rinse the grated potato well until the water runs clear.
Drain the potatoes, and then place them potato on a clean tea towel or several paper towels. Twist the towel to remove as much moisture from the potatoes as possible (you might need to do this in two batches).
Transfer the grated potato to a bowl and toss it with the salt, garlic powder and onion powder.
In a large skillet (preferably cast iron, but non-stick works, too), warm the olive oil over medium heat until shimmering and a piece of grated potato sizzles on contact. Spread the potatoes over the skillet in an even layer and press them down with a spatula. Let them cook, undisturbed, for 2 minutes.
Stir again, press them down again, and cook for another 2 minutes. Repeat in 2-minute intervals, flipping in sections once they’re crispy enough to do so, until the potatoes are golden brown and crispy, about 4 to 8 more minutes. Meanwhile, line a plate with a couple of layers of paper towels to absorb excess oil, and set it near the stove.
Transfer the hash browns to the lined plate and let them drain for a minute. (If you’re making multiply batches of hash browns, repeat these steps as necessary—keep in mind that your skillet will be really hot so your next batch may cook faster.)
Season to taste with additional salt, if necessary, and serve hot.
