Form two tubes of dough into single ring, pinching ends together firmly. Bake according to package directions (but not slashing tops).
Once bread ring has cooled, cut angled trough in top with serrated knife, then pull out more bread to make trough deeper. Place ring on serving plate.
Break or snip rosemary into short lengths. Poke holes in side of bread ring with wooden skewer and insert rosemary sprigs, shorter on top and longer beneath. Place platter in plastic bag and refrigerate until ready to serve.
Fill ring with cheddar cubes and tuck in grape tomatoes.