Place the mini tart shells on a serving dish. Add a teaspoon of raspberry jam into the bottom of each tart shell.
Melt the marshmallows and cream in the microwave on 50% power until melted. Stir until smooth. Spoon the mixture into the tart shells and sprinkle over the desiccated coconut.
The tarts are ready to eat as soon as they've cooled, or can be stored in an airtight container until you are ready to serve them. They are best eaten on the day that they are made.