1. Cut a V shape under stem of each strawberry and discard. Cut berries in half lengthwise across the V to form a heart. Lay berries in a single layer on baking sheets. Freeze until solid, at least 1 hour; flex pan to release frozen fruit.
2. In a 4 1/2-quart or larger bowl, mix cranberry juice cocktail concentrate with sparkling water. Add frozen berries.