Gently pulse all the ingredients in a ninja or food processor. Try mix and not finely chop. You want the chunkiness. Place the brisket in the slow cooker. (Cut the brisket into a few pieces if necessary to better fit in the slow cooker.)
Slowly pour broth mixture over brisket until it’s under the broth. Add more broth if needed to cover meat.
Put the lid on the slow cooker. Cook until the meat shreds easily with 2 forks, 8 to 10 hours on low.