Heat 1 tbsp cooking oil in a pan and add 1 tsp of urad dal and 1 tsp of chana dal when hot. Fry them for a minute.
Now, add 5 cloves of garlic (deskinned) and 2 pieces of green chilies (whole) to it. Again, fry for a minute.
Then, add 2 pieces of cucumber (medium size, chopped roughly). Mix it with the other ingredients nicely. Now, add salt to taste and cook them nicely until the cucumber turns tender.
Transfer the cooked cucumber to a blender.
Add 1 piece of tamarind (small lemon size) and ¼ cup of coriander leaves to it.
Blend it to a smooth paste.
Transfer it to a bowl. Keep it aside.
Now, for making the tempering, heat 1 tsp of cooking oil in a pan and put ½ tsp of mustard seeds in it. Let them crackle.
When the mustard seeds stop cracking, add ½ tsp of cumin seeds (jeera) to it and let them crackle as well.
When they stop cracking, add a pinch of asafetida, 15 pieces of fresh curry leaves, and 1 piece red chili (torn in half). Fry them for a few seconds.
Pour the tempering immediately to the bowl containing the cucumber chutney paste.
Mix and your homemade delicious and cool cucumber chutney is ready to serve.