Step 1

Heat the oven to 190°C/170°C fan/ gas Line 2 large baking sheets with baking paper. Using an electric mixer, beat the 200g butter, 50g icing sugar, plain flour, cornflour, lemon zest and vanilla paste with the 3 tbsp milk in a large mixing bowl until smooth and creamy with a soft, pipeable consistency.

Step 2

Spoon into a piping bag fitted with a star nozzle, then pipe 24 circular swirls, roughly 5cm in diameter, onto the lined sheets, leaving the same size gap between each biscuit. To pipe, start at the outside and pipe a smooth spiral inside, finishing with a gentle squeeze to fill the centre and a smart lift to finish the biscuit. Chill for 15 minutes – or up to 2 hours.

Step 3

Bake in the oven for 16-20 minutes until pale golden and the kitchen is filled with an amazing aroma. Remove from the oven and leave on the sheets for 5 minutes before carefully transferring the whirls to a cooling rack to cool.

Step 4

Meanwhile, make the filling. Using an electric mixer, beat the butter, icing sugar and lemon juice in a large mixing bowl to form a smooth, creamy icing. Taste, adding more lemon if you prefer a zingier icing. Transfer to a piping bag.

Step 5

When the biscuits have cooled, carefully pipe a little icing on the flat side of 12 of the biscuits. Spoon a little jam on top, then top with another biscuit. Sift a little icing sugar over and serve immediately.