In a medium-size saucepan, bring enough salted water to cover the potatoes to a boil. Drop in the potatoes and cook until almost done but still slightly crunchy, about 5 minutes. Drain and reserve.
Heat the oil in a medium-size sauté pan or skillet over medium-high heat until very hot but not quite smoking. Reduce the heat slightly and add the onion and garlic. Cook, stirring often, unt