Put the mochi squares in a food processor and process until finely chopped. Add one avocado, the juice of one lime, and ½ teaspoon salt. Process until combined.
Heat a mini waffle maker, spread some of the mochi mixture evenly in the waffle maker, and cook for 5 – 6 minutes. Repeat with the remaining mixture.
Thinly slice the remaining avocado.
Combine beans, tomato, onion, jalapeno, cilantro, juice of one lime and salt to taste.
Place avocado slices on each waffle and top with the black bean salsa.