Pour vegetable oil into a large, deep skillet or Dutch oven to a depth of about 1 inch. Heat the oil over medium-high heat until it reaches approximately 350°F (175°C). If you don't have a thermometer, test the oil by dropping a tiny piece of tortilla in; it should sizzle immediately and bubble vigorously.

Prepare your forming tools. You will need tongs and a metal ladle or metal bowl slightly smaller than the tortilla diameter to help shape the shells, although forming by hand carefully is also possible.

Carefully place one tortilla flat into the hot oil. Use tongs to gently fold the edges of the tortilla up and over the back of your ladle or bowl so it begins to form a cup shape. Hold it in place for about 30 seconds.

Once the bottom side starts to brown and crisp (about 1-2 minutes), gently flip the tortilla using the tongs or ladle to fully submerge the entire shell for even cooking. Continue frying until both sides are golden brown and uniformly crispy, typically 2-3 minutes per shell.

Remove the finished taco shell from the oil using tongs. Immediately place it on a wire rack lined with paper towels to drain excess oil. While still hot, sprinkle lightly and evenly with salt.

Allow the shells to cool completely on the wire rack (about 10-15 minutes) before using to ensure maximum crispiness. Repeat the process with the remaining tortillas, ensuring the oil temperature is maintained.