- Sprinkle gelatin over 2 Tbsp. water in small saucepan; let stand 1 minute.
- Add sugar; cook, stirring constantly over medium-low heat until gelatin dissolves. Remove from heat.
- Measure watermelon, strawberries and soymilk into blender container. Cover and process on high speed until puréed.
- Pour in gelatin mixture; cover and process on medium speed to combine.
- Strain mixture into large bowl. Cover and refrigerate 2 hours, or until thoroughly chilled.
- Process mixture in ice cream freezer container according to manufacturer’s directions.