Add the onion, Jamie Geller Hawaij, salt, garlic and dates to your slow cooker. Mix until combined then place the beef bones on top.
Prepare 5 cheesecloths into 12 inch squares. Place the stew meat in a cheesecloth, wrap, tie, then place in the slow cooker. Repeat with the wheat berries, chickpeas, potatoes and eggs.
Fill the slow cooker to the top with water.
Cover and cook on low heat for at least 12 hours.
To serve, carefully remove the cheesecloths with tongs, open them, then place each on a serving platter. Remove the marrow bones from the slow cooker and serve the broth on the side. Serve with some spicy schug on the side and everyone can build their own bowl!