Transfer Greek yogurt, cherry extract, stevia, and arrowroot powder and 2 cups of whipping cream to an electric mixer with a whisking attachment. Blend for 2-3 minutes on high speed. Pour the mix in serving glasses and take to the freezer for 30-40 minutes.
Boil the gelatin with a cup of water. Stir well to dissolve the gelatin completely. When done, remove from the heat and allow the gelatin to cool to room temperature.
Chop the avocado into bite-sized portions after slicing them in half and peeling off the skin. Put aside for later.
Add 2 tablespoonful of gelatin on top of the frozen yogurt. Put some avocado chunks as well. Put in the rest of the whipping cream and replace in the freezer for another 15 minutes.