Step 1: Prep and Season the Ribs - Start by patting the ribs dry with paper towels. This helps the seasoning stick better and keeps the sauce from getting watered down. Sprinkle the salt, pepper, and garlic powder evenly over both sides of the ribs. I like to rub the seasoning in gently with my hands so every bite gets flavor. If your rack of ribs is too large for the slow cooker, go ahead and cut it into smaller sections.
Step 2: Arrange the Ribs in the Slow Cooker - Place the seasoned ribs into the slow cooker. You can stand them up along the sides or layer them slightly if needed. Do not worry if they look crowded because they will shrink down as they cook. The important thing is making sure the ribs are nestled down into the cooker so they stay moist and tender.
Step 3: Make the Root Beer BBQ Sauce - In a medium bowl, stir together the root beer, barbecue sauce, brown sugar, and Worcestershire sauce until smooth. Right away you will notice how rich and sweet the sauce smells. Pour half of the mixture over the ribs, saving the rest for brushing later. The sauce will slowly soak into the meat as it cooks, giving every bite incredible flavor.
Step 4: Slow Cook Until Tender - Cover the slow cooker and cook the ribs on low for six to eight hours or on high for four to five hours. I personally think low and slow gives the best texture because the meat gets unbelievably tender. By the end of cooking the ribs should be soft enough that the meat nearly pulls away from the bone on its own.
Step 5: Transfer the Ribs Carefully - Once the ribs are done, carefully lift them out of the slow cooker and place them on a foil lined baking sheet. Be gentle here because the ribs will be very tender and can fall apart easily. I usually use two large spatulas to support them while moving them.
Step 6: Brush and Broil the Ribs - Brush the ribs generously with the remaining sauce along with some of the sauce from the slow cooker. Place the baking sheet under the broiler for about three to five minutes. Keep an eye on them because the sugars in the sauce caramelize quickly. You want the edges sticky, bubbling, and slightly charred in spots.
Step 7: Finish and Serve Warm - Once the ribs come out of the oven, brush them with one more layer of sauce for extra flavor and shine. Let them rest for a couple of minutes before serving. That short rest helps the sauce settle onto the ribs beautifully. Then dig in while they are hot and sticky.