Transfer ribs to a 6-qt slow cooker. Distribute evenly on the bottom.
In a large bowl, whisk together: soy sauce, beef broth, brown sugar, minced garlic, ginger, sesame oil, Worcestershire sauce, and red pepper flakes. Stir until well combined.
Add the mixture to the slow cooker over the ribs. Add the 10 whole garlic cloves, distribute evenly, also between the ribs. Same for the quartered onion and bay leaves. Top with whole dried chili peppers.
Cover and cook on low heat for 8-9 hours or high heat for 4-5 hours.
If you can, mid cooking, using a ladle, pour some of the slow cooker sauce on top of the ribs.
Once cooked, in a small bowl, whisk together cornstarch and ¼ cup water until fully combined, with no clumps. Gently stir in the mixture into the slow cooker. Cover and cook on high heat for an additional 30 minutes, or until the sauce has thickened.
Garnish with parsley and sesame seeds. Serve and enjoy!