Preheat the oven to 180°C/ 160°C fan/ gas mark 4/ 350°F
Prepare the icing bag: Snip off the end and put the nozzle in so that it fits comfortably. Fold back the open edge so that you have a cuff. That way the mixture doesn't get stuck at the top
Put 18 paper cases in the bun tinsYou may need a couple more, so be prepared
For the tarts:
Put all the ingredients in a large bowl and beat well until smoothEasiest with a hand or stand mixer
Spoon the mixture into the icing bag and pipe a circle into each paper case. The mixture won't cover the base of the case, but it will expand as it's cooked
Bake in the oven for 20-25 minutes or until a pale golden colour
Leave to cool on a wire rack
Put a small amount of jam in the centre of each tart. Dust with sifted icing sugar
Notes
Swiss Tarts keep for at least a week in an airtight container. They don't need to be refrigerated.