Add chana dal to a bowl and wash it with lot of water a few times.
Soak it in good amount of water for 2 hours. Drain completely. Chana dal must be fully tender and soaked without any hard center.
Add cinnamon, red chili, jeera and saunf to a blender jar. Make a coarse powder. Keep this aside with 2 tbsp soaked chana dal.
Next add the drained chana dal & salt to the same blender jar.
Pulse it a few times until it turns to a coarse mixture. The dough must have some uncrushed chana dal. Transfer to a bowl.
Next add finely chopped mint, curry leaves, onion, masala powder we just made above.
Also add green chilies and ginger garlic paste. Mix everything well. Taste and add more salt if needed.
Take a handful of the dough & check if it binds well. To check make a ball & then flatten it to a masala vada. The mixture must have a good binding to shape them to vadas.
Remove this to your fingers & check if the masala vada is binding well. If the mixture doesn't bind well, then take a handful of this mixture and blend to a smooth paste.
Mix that with the rest of the dough.
Heat oil in a deep pan on a medium flame.
While the oil heats, divide the dough to 10 parts.
Make small balls and flatten them on your palm. You can also make these on a greased plastic sheet or dry cloth.
Check if the oil is hot enough by gently dropping a small portion of the dough to the oil. The dough must rise without browning quickly. This is the right temperature.
Slide masala vada one by one gently to the hot oil. You can add about 3 to 4 vadas in each batch.
Do not disturb them immediately otherwise they will break. Wait until they firm up for 2 to 3 mins before turning them over to fry the other side.
On a medium flame deep fry the masala vadas until golden & crisp on both the sides.
Transfer the masala vadai to a kitchen tissue. Fry the rest of them in batches following the same procedure.
Serve masala vada hot with coconut chutney or ketchup.
If your air fryer needs preheating, then preheat it for 15 mins at 180 C or 350 F. Place the masala vadas on the rack. I don't brush mine with oil or ghee in the beginning. You may do if it is okay with your air fryer.
Air fry for 10 mins at 180 C or 350 F. Turn them to the other side and air fry for another 6 to 7 mins. Please adjust the time as needed depending on your air fryer. They will turn hard if you over fry them. Once done brush the air fried masala vadas lightly with oil or ghee.