Mint Lime Watermelon Kefir Slushie

For the watermelon kefir juice:
Blend watermelon cubes with mint leaves until smooth. Pour through a fine-mesh strainer over a large bowl to collect the juice. Discard pulp.

Pour watermelon juice into a glass jar and add water kefir. Cover with lid and let it stand at room temperature for at least 18 hours.

For the watermelon slushie:
Line baking dish with parchment paper and then place diced watermelon cubes into baking dish. Freeze 4 hours until firm.

Add all watermelon slushie ingredients into a blender. Blend until smooth. Garnish with mint sprigs and serve immediately. If desired, add natural sweetener, such as pure stevia extract powder, for extra sweetness.