Preheat your oven to 300°F (150°C).

Slice the ripe plums in half and coat with brown sugar. Place cut-side up in a baking dish and roast for 15-20 minutes.

Mix the gelatin with 2 tablespoons of water and set aside to soften.

In a saucepan, combine whole milk, heavy cream, granulated sugar, and salt. Heat until sugar dissolves without boiling.

Once plums are roasted, blend them with their juices into the milk mixture until smooth.

Pour the softened gelatin into the plum mixture, stirring thoroughly to combine.

Chill the mixture in the refrigerator until it reaches 40°F (4°C).

Churn the mixture in an ice cream maker according to the manufacturer's instructions for 20-30 minutes.