Preheat the oven to 170C/325F/Gas 3.
In a bowl, rub together the butter, sugar, vanilla seeds and flour, using your fingertips.
Bring the mixture together to form a dough, turn out onto a lightly floured work surface and knead until the dough is smooth. Roll into a ball, then wrap the dough in cling film and chill in the fridge for at least 15 minutes.
When the dough has chilled, roll it out onto a lightly floured work surface until it is about 6mm thick.
Cut 7.5cm/3in discs from the dough using a cookie cutter or upturned mug.
Divide the pastry discs into two portions. Cut a small 1.5cm/1¾in heart shape from each disc in the first portion using a shaped cookie cutter or sharp knife. Leave the remaining pastry discs whole.
Lightly grease a baking tray and place all of the discs onto it. Bake in the oven for 12-15 minutes, or until crisp and pale golden-brown. Remove from the oven and place onto a wire rack. Set aside to cool.
When the biscuits have cooled, place one teaspoonful of clotted cream onto each of the whole biscuits. Spoon a small dollop of jam on top of the cream. Place the biscuits with the heart-shaped holes on top and gently squeeze together.