Make the crust according to its directions here except use four 4.75 (12 cm) mini tart pans.
Preheat the oven to 160 °C/ 325 °F.
Make the cake by processing all of the cake ingredients in a food processor until combined.
Fill the tart pans with the batter.
Using foil cover the edges of the tarts so they wont burn.
Bake the tarts for 30 minutes until the cake is set.
Remove from the oven and allow to cool on a wire rack.
Remove the tarts from the pans before frosting.
While the tarts are baking make the frosting by beating the avocado, powdered sweetener and heavy cream in a stand mixer fitted with the whisk attachment on high for 3-4 minutes.
The frosting should be stiff and easily pipeable.
Transfer the frosting to a piping bag or a plastic baggie and snip of the corner.
Pipe the frosting onto the tarts then top with fresh raspberries.
Note: To prevent the avocado from browning, add some lemon or lime juice to the frosting, and keep in an airtight container in the fridge for up to 4 days.