Pour the rosé wine into ice cube trays and freeze for at least 6 hours or overnight.
When you're ready, toss the frozen rosé cubes into the blender.
Add the frozen strawberries, simple syrup, lemon juice, and grenadine.
Blend on high until smooth and slushy. Add ice as needed to get the texture you want.
If it's too thick, splash in a bit of unfrozen rosé or even water.
Pour into chilled glasses.
Garnish with fresh berries and mint sprigs.
Serve right away for the best texture.