Wash the ripe plums under cold running water, slice them in half to remove the pits, and chop into small pieces.

In a medium saucepan, combine equal parts water and granulated sugar over medium heat, stirring continuously for about 5 minutes until the sugar is dissolved.

Once the syrup has cooled slightly, stir in the ground cardamom and a pinch of salt. Let sit for about 10 minutes.

In a blender, combine the cooled syrup, chopped plums, and lemon juice. Blend on high speed until smooth, about 30-45 seconds.

For a finer texture, strain the mixture through a fine mesh sieve into a bowl.

Cover the bowl with plastic wrap and refrigerate for 1 to 2 hours.

Pour the chilled mixture into the ice cream maker and churn for about 20-25 minutes until it reaches soft-serve consistency.

Transfer the churned sorbet to a lidded container and place it in the freezer for at least 4 hours.

When ready to serve, scoop into bowls and garnish with fresh mint leaves or additional cardamom.