Gently toss avocado with 1 tablespoon of the lime juice in a medium bowl. Add mango and jalapeño and gently toss to combine. Set aside.
Whisk together remaining 2 tablespoons lime juice, zest, cilantro, salt, pepper and sugar in a large bowl. Whisk in oil until thoroughly combined to make a thick dressing. Add avocado mixture and black beans and toss gently. Spoon salad onto plates, garnish with cilantro and serve immediately.