If time allows, chop the ripe mango into small cubes and freeze them before making the lassi for the best texture and flavor.
Add the mango, yogurt, milk, mango pulp (start with the lower amount), sugar (start with the lower amount), and ice cubes to a blender.
Blend on high until completely smooth and no longer icy.
Taste and adjust. Add more sugar for sweetness, more mango pulp for stronger mango flavor, or a tablespoon of yogurt for more tang.
Pour into glasses, garnish with mango cubes or mint if desired, and serve immediately.