Soak 1 cup rolled oats in water for 10 to minutes.
Boil 1 cup fresh or frozen green peas with ½ teaspoon salt . Make sure to cook green peas completely.
Add soaked oats, green peas , ginger, dry red chili, cumin seeds, carom seeds , asafoetida and hing into a mixer. Blend to a smooth batter by adding ¼ to ½ cup water.
Transfer to a bowl , add chopped onions and coriander leaves, Mix well together.
Heat tawa/ pan/ griddle , spread ladle full of batter on tawa .
Drizzle oil ( for vegans) or ghee .
Cover lid and cook for 2 minutes.Flip and cook on both sides.
Serve with any chutney or curry. I usually pair Oats chilla with Tomato chutney or Pumpkin Chutney.