Cut lengthwise around middle of avocado; twist avocado to separate halves; strike pit with a knife blade to remove; scoop out pulp with a spoon.
In a small bowl, mash avocado.
To assemble tortas: Spread mashed avocado on cut sides of rolls, dividing evenly. Sprinkle with salt and pepper. On bottom halves, layer sliced chicken, lettuce, tomato, black beans and jalapeÒo pepper slices. Firmly press tops of rolls on tortas.
1 fully ripened Mexican avocado
2 (6-inch) sandwich rolls (such as Portuguese or submarine rolls), halved Salt and freshly ground black pepper, to taste
8 ounces grilled chicken breast, sliced
1 cup shredded iceberg or romaine lettuce
1 tomato, sliced
2/3 cup mashed black beans, divided
1/4 cup pickled jalapeno pepper slices