1 Preheat the oven to 180 ºC. Line two baking sheets with baking paper or silicone mats.
2 Mix the flour, baking powder and salt together in a bowl.
3 In another bowl, cream the butter and sugar until creamy. Beat in the egg and vanilla essence until just combined.
4 Slowly beat in the dry ingredients in two batches, mixing until just combined.
5 Roll the dough into balls and place them on the prepared baking sheets. Press a thumbprint into the centre of each ball and fill each hole with jam.
6 Bake for 10 minutes or until the edges of the biscuits are golden.