Wash and soak the chana dal for 2 hours.
Drain the water and keep 1 tbsp of soaked chana dal aside.
In a mixie jar, add the red chilis, curry leaves, ginger, garlic, fennel seeds.
Pulse this first.
Now add the soaked chana dal to the mixie jar.
Pulse this into a coarse paste.
Do not add any water.
Transfer this to a bowl.
Just before making add finely chopped onions, baking soda, 3 tsp oil and salt.
Mix well evenly.
Line a baking tray with a baking sheet r aluminum foil.
Grease your hands with oil and take a lemon sized dough.
Make a thin patty, do not make a thick one, it will not get baked inside.
Preheat the oven at 170 degrees for 10 minutes.
Arrange all the dough patties in the tray.
Drizzle little oil on the patties.
Bake this for 25-30 minutes at 170 degrees.
Mine got done in 25 minutes.
Baking time varies from oven to oven.
Enjoy the crispy masala vadas hot.
Serve with any chutney of your choice or you can enjoy this with curd rice too.