Grate 200g of fresh cucumber using the coarse side of a box grater into a bowl.
Sprinkle 1/4 tsp salt over the cucumber, stir, and let it sit in a mesh strainer for 5 minutes to release its water.
Firmly squeeze the grated cucumber with your hands or a clean kitchen towel to remove excess liquid.
In a medium bowl, whisk 1 cup of cold yogurt until perfectly smooth and creamy.
Add the squeezed cucumber, roasted cumin powder, black salt, and a pinch of sugar to the yogurt. Mix gently.
Fold in the chopped mint and cilantro. Chill in the refrigerator for 15 minutes before serving. Garnish with a pinch of cumin and chili powder.