Highly Recommended Step: soak chickpeas, beans & wheat berries overnight in a bowl of water. Not a necessary step, the soup works fine without pre-soaking – but the pre-soaking reduces some of the bitter aftertastes of the grains many give to the soup.
Rinse the chickpeas, beans & wheat berries in cold water. Add to your instant pot and fill with water to cover the beans by two inches. Close the lid on the Instant Pot. Use the multi-grain setting and time it for 20 minutes. Once the time has finished, allow for a 7-10 minute slow release.
While you wait for your beans to be done, start soaking the bulgar, rice and lentils in cold water.
Saute the onions for stew: In a large frying pan heat the ¼ cup of olive oil over medium-high heat. Add all of the chopped onions ⏤ fry until dark brown and soft. Once the onions are finished add the cumin & salt.
Finished beans: release the pressure from the Instant Pot. Open lid. Drain the lentils, rice, & bulgar. Then add them to the bean mixture along with the potato. Stir. Add salt. (you may need more water. The water should cover the grains by 2 inches.)
Reset the Instant Pot back onto the multi-grain setting and cook for 10 minutes. Once cooking time is finished allow for a 7-10 minute slow release.
Finish the soup. Once the grain base is finished, open the lid of the Instant Pot. Add all the onions and olive oil to the bean soup. Adjust water & salt. (The soup should not be runny or too dry, it should be somewhere in-between). Allow the soup to sit for 10 minutes to cool and for the flavours to set.
While the soup is cooling. Use the frying pan you used for the chopped onions. Reheat over medium-high heat. Add 1 tablespoon of olive oil and all the sliced onions ⏤fry until dark brown and crispy. Stir often.
Serve. Ladle some soup into a bowl and top with some fried onions. Enjoy.