Adjust oven rack to center position and preheat oven to 375°F (190°C). Heat oil in a large wok or Dutch oven to 350°F (175°C). Add ⅓ or tortilla chips and cook, agitating and flipping them constantly with a wire mesh spider until bubbles slow to a trickle and chips are pale golden brown, about 2 minutes. Transfer to a paper towel-lined bowl, season with salt, and toss. Allow to drain for 30 seconds, then transfer to a second bowl. Repeat with remaining chips in 2 more batches.
Layer ⅓ of chips in the bottom of a large cast iron skillet or baking dish. Dollop with ⅓ of chili and ⅓ of refried beans. Drizzle with ⅓ of cheese sauce, then sprinkle with half of black beans.
Layer with another ⅓ of chips. Dollop with ⅓ of chili and ⅓ of refried beans. Drizzle with ⅓ of cheese sauce, then sprinkle with remaining half of black beans.
Layer with remaining ⅓ of chips. Dollop with ⅓ of chili and ⅓ of refried beans. Drizzle with ⅓ of cheese sauce. Transfer to oven and bake until edges of chips are well browned, about 5 minutes. Remove from oven.
Top with half of salsa, tomatoes, olives, jalapeños, radishes, scallions, onions, cilantro, and a big dollop of guacamole. Serve immediately with remaining salsa and guacamole on the side.
