Pour enough oil into a skillet to lightly fry the tortillas one at a time, just until they soften. Do not let them get crispy. Drain off any excess oil and set aside.

For the bean sauce:
Blend the beans. In a large saucepan, heat oil and add the 1/4 onion. Fry until golden, then add the blended beans. Adjust the salt to taste.

Once the beans are seasoned, quickly dip each tortilla in the hot bean sauce so they are coated but not falling apart. Place them on a plate.

While the tortillas are still warm, fill each one with shredded chicken and roll them up like tacos. Repeat with all the tortillas.

To serve, place the rolled tortillas on a flat plate and pour some hot bean sauce over them. Top with sour cream, cheese, and chopped onion as desired.

Garnish the plate with sliced lettuce, radish slices, and avocado on the side.