1/4cuplight soy sauce(or use a gluten-free alternative and add salt as needed)
1teaspoonDiamond Crystal kosher salt
Place the ribs in your slow cooker. If you bought a slab like I did, you'll probably need to cut it in half with a sharp chef's knife to fit in your slow cooker.
In a medium bowl, whisk together the remaining ingredients except for the cornstarch. Pour over the ribs, and use your clean hands to rub the sauce into the ribs, on all sides.
Cover and cook on LOW for 6 hours, until the meat is fall-apart tender (and smells amazing!).
Set the slow cooker to WARM. Transfer the cooked beef ribs to a plate for a minute. Strain the liquids from the slow cooker into a wide saucepan, then return the ribs to the slow cooker and cover, to keep them warm while you reduce the cooking juices into a glaze.
Heat the strained cooking juices on medium-high. Whisk the cornstarch with a little cold water and add to the saucepan. Keep cooking on medium-high, whisking often, until the sauce has thickened into a rich glaze, 5-10 minutes. Brush over the ribs and serve.