Spritz slow cooker insert with olive oil or non-stick cooking spray.
Arrange the rack of ribs by standing them on their ends around the edges of the insert.
Pour about 3/4 cup of the BBQ sauce over the ribs, place the lid onto the slow cooker and set the timer for 8 hours on low or 4 hours on high.
Before serving, remove the ribs from the slow cooker and cut into individual ribs. Brush with additional BBQ sauce, about 1/4 cup. Serve on a platter with remaining sauce.
Notes
If the membrane on underside of the ribs has not been removed by the butcher, I always remove before I cook the ribs. To make ahead. Prepare as directed. Cool and store in an airtight container in the refrigerator for up to 4 days.To freeze. Prepare as directed, cool completely, and store in a freezer-safe, airtight container in the freezer for up to 3 months.