For some of the readers residing outside Pakistan, you would have Greek yogurt available. For those in Pakistan, it is not much of a big deal and is very easy to replicate in desi-land. (Psssst, residing abroad people, you can follow the next step too, to make the recipe pocket friendlier than it already is).
Take some plain yogurt (we in desi-land get our yogurt from the yogurt shops found easily in every corner of the city). Take a piece of cheese cloth. Wet it and wring out the water. Beat the yogurt to make it smooth. Pour the yogurt over the cloth. Bring the corners together and tie the cloth. Place on a strainer and put the strainer in a bowl such that there is lots of space below it to catch the water. Leave in the refrigerator for an hour or two.
If you are impatient like me, press the yogurt in the cloth to remove water, until the yogurt of desired consistency is left. If you let water drip out itself, you can use the leftover water in cakes or pancakes. If you press out the water, I'd rather not use it in anything, because after all it sounds gross.
The yogurt in the cloth would be thick like Greek yogurt. You can use it in the recipe mentioned.
500 gm yogurt (remove water as mentioned above)
1 - 2 cucumbers, cut into small pieces
3 tbsp green coriander, chopped finely
1 tsp dried mint leaves, rubed into a powder
Salt, to taste
Black pepper, to taste
Mix all ingredients in a bowl. Taste and adjust seasoning. Chill thoroughly before serving. Simple and easy. Happy cooking!!!