Crisp-Fried Tostadas (Tostadas Fritas)

Heat the oil in a deep skillet over medium to medium-high until it reached 360 degrees (a thermometer is essential for consistently crispy tostadas, but lacking one, hot oil will look shimmery and the edge of a tortilla will sizzle sharply when dipped into it). Fry the tortillas–for consistency, I fry them one at a time–flipping them regularly, until they darken and are rigid, about 30 seconds to 1 minute. Drain on paper towels. Sprinkle with salt while they are still hot.