Cut 2 lb. (900 g) baking potatoes into wedges, cutting each potato into 4 wedges. Spread onto rimmed baking sheet. Drizzle with 2 Tbsp. oil; sprinkle with 1 tsp. seasoning salt. Bake in oven along with the ribs. Transfer to barbecue with ribs after 1 hour. Grill 20 min. or until potatoes are tender, turning after 10 min. Serve with ribs.
If you don't want to use your barbecue, omit the grilling step. Prepare recipe as directed, increasing baking time to 1 hour 15 min., turning and brushing both sides of ribs occasionally with barbecue sauce for the last 15 min.