Cream together the butter and icing sugar in a large mixing bowl using a wooden spoon or electric mixer.
Add the vanilla extract and the flour and mix until you have a soft dough.
Wrap the dough in cling film and place in the fridge for 15-30 minutes.
Preheat the oven to Gas Mark 4 or 180 degrees and line two baking sheets with baking paper.
On a floured surface, roll out the biscuit dough and use circular cutters (I used the crimped side) to cut out your biscuit shapes. In every other circle, I cut out a heart using a small cutter (for the tops).
Bake in the oven for 10-12 minutes or until all of the biscuits are starting to look golden.
Place the biscuits onto a wire rack to cool.
Spread a half a teaspoon of strawberry jam onto the base biscuits, starting in the centre then spreading out, then place the cut out biscuit on top.
Dust the biscuits with icing sugar to serve.