HEAT the oil in a large skillet over medium-high heat until shimmering. Add the beans and spread out into a single layer. Cook without stirring until lightly browned on the bottom, 3 to 4 minutes. Stir, add a big pinch of salt, and spread the beans out again. Cook for another 2 minutes, then stir and spread out again as needed, until golden-brown and blistered on all sides. From start to finish, this will take about 6 to 7 minutes total.