Add 2-4 cups of water in the pot of Instant Pot. Place Steamer Rack Stand at the bottom of the pot and put IP on saute mode. Let the water come to boil while you prepare for the batter. If you have whole gluten free rolled oats, process them in a food processor to make flour, it does not have to be super fine or super grainy. Something in between would be best!
Chop coleslaw in a food processor. Place the finely chopped coleslaw in a big wide bowl.
Add oats flour, chickpea flour and all other ingredients listed above in the same bowl.
Check on the water in IP, once it starts to boil, start kneading the dough/batter. The water from coleslaw should be enough to form the dough/batter. If it is not coming together, use 1 tsp water at a time to make the dough. But be very careful with adding water as the coleslaw should have more than enough water and it will keep loosing more as you knead the dough. With the exact measurements, you should not need any extra water to form the dough.
The dough should be soft enough to make a cylinder like shapes using your hands. Take some oil between your palms if it is super sticky.
Place cylinder shaped dough in a greased stailes steel plates/thali, thali with a little less diameter than IP diameter.
Once you are done with making all the dough cylinders, Turn the saute mode off.
Place the prepared plate/thali inside the Instant Pot on top of the Steamer Rack Stand. Be careful with this step as the water is boiling inside the IP at this point. Close the IP lid. If it is not closing easily, make sure you open the valve then close it.
Once closed, secure/seal the valve. Put IP on steam mode for 20 minutes. If your IP model does not have timer on it, just use some external timer to steam it for 20 min.
Once timer goes off, let the pressure release for 15-20 minutes. Release rest of the pressure manually.
If using Indian style steamer, steam the muthiya in there with decent amount of water at the bottom for 25 minutes.
Once the valve is vented, carefully take the thali out and let it cool down for 10-15 minutes.
Once cooled down to handle, cut them in decent size pieces.