Take yogurt in a bowl. Add salt, pepper, roasted cumin powder, red chili powder and black salt. Whisk it until yogurt is smooth and spices are mixed well.
Add grated cucumber and mint leaves. Mix using a spoon.
Cover it with plastic wrap. Store in the refrigerator until the time of serving. Raita tastes best when served chilled.
Video
Notes
Homemade roasted cumin powder: Dry roast the cumin seeds on medium-low heat by stirring constantly until aromatic and the seeds are darker in color. Let them cool down and then grind into a powder using a spice grinder or mortar and pestle.
Storing cucumber raita for more than a day (24 hours) is not advisable. Cucumber will leave its water after storing and it makes the raita watery and runny. Plus, cucumber will lose its crunch and freshness.
I prefer to use Persian or English cucumber as they have thin skin and almost no seeds. If your cucumber has thick or tough skin then you should peel the skin.