Wash the rice, then soak in water for at least 30 minutes, or overnight.
Drain the water & grind the rice in a food processor or high-speed blender, adding a little fresh water to form a thick smooth paste.
Blend cucumber &coconut in a food processor until a pasty consistency is formed
Add cucumber &coconut, chilis, ginger & salt to rice paste and mix well. Batter should be medium thick consistency.
Heat a non-stick griddle or pan.
Pour a ladle full of batter and spread lightly on the pan. Drizzle oil on top.
Cover with a lid and cook until the base turns golden brown, 1-2 minutes.
Flip and cook other side for 30 seconds.
Repeat steps 6-8 for each dosa.