Quarter potatoes, rinse well under cold water. Drain well, spread on a clean kitchen towel and dry well.
Heat oil in a very large skillet over medium-high heat until it shimmers. Add potatoes, cut side down, in a single layer. Cook without stirring, 5-7 minutes, until golden brown. Oil should sizzle but not smoke.
Turn onto other cut side and cook 5-6 minutes, until a deep golden brown.
Stir potatoes and redistribute in a single layer. Reduce heat to medium-low, cover, and cook 6-9 minutes, until tender.