Mary's Viennese Whirls

Ingredients

For the jam:

• 200g/7oz raspberries
• 250g/9oz jam sugar

For the biscuits:

• 250g/9oz very soft unsalted butter
• 50g/1¾oz icing sugar
• 225g/8oz plain flour
• 25g/1oz cornflour

For the filling

• 100g/3½oz unsalted butter, softened
• 200g/7oz icing sugar, plus extra for dusting
• ½ tsp vanilla extract

Method

For the jam, put the raspberries in a small, deep-sided saucepan and crush them using a potato masher. Add the sugar and bring to the boil over a low heat. When the sugar is melted, increase the heat and boil for a further 4 minutes. Remove from the heat and carefully pour into a shallow container (pass it through a sieve if you'd rather not have seeds in your jam). Leave to cool and set.

For the biscuits, preheat the oven to 190C/170C Fan/Gas 5. Line 3 baking sheets with non-stick baking parchment. Using a 5cm/2in round cutter as a guide, draw 8 circles on each sheet of paper, spaced well apart. Turn the paper over so the pencil marks are underneath.

Measure the butter and icing sugar into a bowl and beat until pale and fluffy. Sift in the flour and cornflour and beat well, until thoroughly mixed. Spoon the mixture into a piping bag fitted with a medium star nozzle. Pipe 24 swirled rounds (not rosettes), inside the circles on the baking sheets.

Bake in the centre of the oven for 13—15 minutes, until a pale golden-brown. Cool on the baking sheets for 5 minutes then carefully transfer to a wire rack to cool completely and harden.

For the filling, measure the butter into a bowl and sift the icing sugar on top. Add the vanilla extract and beat with a wooden spoon or an electric whisk until very light and smooth. Spoon into a piping bag fitted with a large star nozzle.

Spoon a little jam onto the flat side of 12 of the biscuits and place jam-side up on a cooling rack. Pipe the buttercream over the jam and sandwich with the remaining biscuits. Dust with icing sugar to finish.