Preheat oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a large bowl, cream together the butter and sugar until light and fluffy (about 2-3 minutes).

Beat in the egg and vanilla extract until smooth.

In another bowl, whisk together flour and baking powder; gradually add to the wet mixture, mixing on low speed until just combined.

Spread half the dough onto one side of the prepared baking sheet. Spoon dollops of raspberry jam over it and swirl gently with a knife.

Bake for 12-15 minutes or until edges are lightly golden. Cool on a wire rack.