Peel the potatoes and grate them on the big-holed side of the grater. In a fine-mesh sieve, rinse the grated potatoes well until the water runs clear.
Drain the potatoes, and then place them on a clean tea towel or several paper towels. Twist the towel to remove as much moisture from the potatoes as possible.
Transfer the grated potatoes to a bowl and toss them with the salt, garlic powder and onion powder.
In a large skillet, warm the olive oil over medium heat until start to shimmer 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 about 2 minutes.
Stir again, press them down again and cook for another 2 min. Repeat in 2-min intervals for about 4 to 8 more minutes. Meanwhile, line a plate with a couple of layers of paper towels to absorb the excess oil and set it near the stove. Transfer the hash browns to the lined plate and let them drain for a minute.
Season to taste with additional salt, if necessary, and serve hot.
