Stir yogurt briskly in a bowl to make sure it is smooth.
Mix in mint, salt, and cumin.
Add cucumber. Stir well.
Refrigerate for several hours for best flavor.
Place in a serving dish. Grind a bit of black pepper over the top.
Garnish the raita with mint and/or cilantro leaves. Serve cold in small bowls.
This dish typically features dairy yogurt, but for a vegan version, experiment with unsweetened plant-based alternatives.