Peel and quarter your onion and peel your carrots. Add them to a food processor and process until finely chopped. If you do not have a food processor, you may finely chop by hand. Then transfer them to a large pot.
Add all remaining ingredients except the spinach to the same pot and bring to a boil over high heat. Then lower the heat to medium-low and simmer with the lid on, but slightly askew for 30-40 minutes until the barley and beans are tender.
Turn off the heat and stir in the spinach. The spinach will wilt quickly and then serve.
Notes
To soak your beans overnight, cover them with cool water two inches above the beans to allow room for them to grow. Drain when ready to use.If you did not soak the beans overnight, boil some water in a pot or kettle and cover the beans with the boiling hot water for 30 minutes. Then drain and use as directed.To make the soup gluten free, you may use brown rice instead of barley.Leftovers keep refrigerated for 3-4 days or freeze them airtight for up to 3 months.