- Place agar in a saucepan with juice.
- Bring to a boil and cook, stirring frequently, over medium heat for 10 to 15 minutes.
- Add vanilla and cook for one minute.
- Cut all but 6 strawberries in half.
- Place cut strawberries in a shallow pan and pour hot mixture over them.
- Place pan in freezer until set, about 30 minutes.
- Cut jellied juice and strawberries into 2" squares.
- Place 2 squares and cashew butter in a blender and process until smooth.
- Remove mixture to a bowl and blend remaining squares, 2 at a time until smooth.
- Whisk blended mixture to evenly distribute cashew butter throughout.
- Place into individual serving bowls.
- Slice remaining strawberries and evenly divide among bowls.
- Refrigerate until set, about one hour, or place in freezer for 15 to 20 minutes.