Taken from the second series of The Great British Bake Off, these delicious melting moments are the perfect recipe to test your baking skills
250g unsalted butter, softened
60g icing sugar, sifted
½ teaspoon vanilla extract
250g plain flour
Red food colouring (the gel type works best)
Icing sugar, for dusting
For the filling
125ml full-fat or semi skimmed milk
2 tablespoons plain flour
125g caster sugar
125g unsalted butter, softened
½ teaspoon vanilla extract, or less to taste
about 2 tablespoons seedless raspberry jam
You will also need: 2 baking sheets, lined with baking paper; a piping bag fitted with a star tube
If the filling mixture is very soft, cover and chill until it is firm enough to pipe.
Using a wooden spoon or electric mixer, beat the butter with the icing sugar until pale and fluffy. Add the vanilla and beat for a few seconds. Sift the flour and cornflour together into the bowl and mix until smooth.
Paint a straight line of red food colouring on the inside of the piping bag, from the tube to the opening of the bag. Spoon the biscuit mixture into the piping bag.
Pipe into 32 swirls on the baking sheet. Each swirl should be about 5cm across and 2.5cm high. Chill in the fridge or freezer for 15 minutes to firm.
Meanwhile, preheat the oven to 180°C/350°F/gas 4. Bake the biscuits for about 12 minutes or until they are pale golden. Leave for a few minutes on the baking sheet to set slightly before transferring to a wire rack to cool.
To make the filling, heat the milk with the flour in a small pan, whisking constantly until the mixture boils and thickens. Whisk over very low heat for a minute to cook out the taste of the flour, then pour the mixture onto a plate. Cover closely with clingfilm to prevent a skin from forming and leave until completely cold.
Beat together the sugar and butter until very pale and fluffy – about 10 minutes by hand or 4 minutes with an electric mixer. Add the thickened milk mixture and beat until light, creamy and almost white. Add the vanilla.
To assemble, spread a little jam on the bases of half the biscuits. Pipe small swirls of the filling onto the bases of the remaining biscuits and sandwich pairs together. Lightly dust with icing sugar.