Heat oil in a pan and add crushed ginger. Saute for 10 seconds.
Then add onion and saute for 3-4 minutes on medium flame.
Now add sliced salad cucumber and saute for again 3-4 minutes. Add salt as required in this stage.
Pour yogurt and mix well. Turn off the flame.
In a separate pan, prepare the tempering by heating a little oil and splutter mustard seeds. Add green chilly, curry leaves and dry red chilies. Top it over the curry and enjoy!