Wash and soak the rice and dal , separately for 6 hours.
Using water as needed, Grind to smooth batter and keep overnight to ferment.
Add the oats too while grinding.
Add salt as per taste and keep for fermentation overnight.
Next morning, heat up a non stick pan or Tawa.
Take about 2 heaped tablespoons of the batter and spread in a circle.
Sprinkle all cut vegetables on top.
Cook on low flame.
Flip and cook the other side as well.
Remove when done and using a round cookie cutter, cut out rounds.
Serve as sandwiches after applying any chutney and stuff with vegetables like cucumber and carrot.
Uttappam-Veg-Sandwiches are ready to be served as finger food.