In an oiled grill pan, toss the beans with oil and salt.
Now, place the pan grill on the grill and stir until the beans turn black. Stir it for few minutes and then, remove it from the grill and get aside.
Now, take some tortillas and place them on the grill. After some time, their edges will start to curl from heat.
Then, sprinkle some cheese on them. Remove the tortillas from the grill when they become hard and crunchy. Top them with beans, onion, salsa, and guacamole.
Roast them in the oven at 400oF for 15 minutes. Stir them every 5 minutes. Dress them with cheese and return them to the oven. Once the cheese melts properly, take them out from the oven and set them aside.