Add the raisins to a bowl and pour over the rum. It is best to do this the night before so they have time to soak very well, but you can also do it at the beginning of making these cookies.
Begin by lining a baking sheet with parchment paper.
Use an electric mixer to cream together the butter and cream cheese until smooth.
Gradually add the sugar and beat the mixture for about a minute.
Incorporate the egg and extract and continue beating until well combined.
Gradually add the baking powder and flour.
Once all ingredients are incorporated, transfer the dough to the refrigerator and chill for at least an hour.
Preheat your oven to 375F (190C).
Since the dough can be sticky, dust your hands with flour before rolling it into 1-2 inch balls.
You can gently flatten the balls using the bottom of a cup or glass dipped in flour, being careful not to flatten them too much as this may prevent the cookies from puffing up.
Bake the cookies for 10-15 minutes, making sure to remove them from the oven when you notice the underside edges turning golden. Keep a close eye on the cookies, as baking times may vary.
Once done, let them cool and prepare the filling by mixing together the cream cheese with powdered sugar, then adding the rum-soaked raisins.
Spread the filling on each cookie and you can serve them by making little cookie sandwiches.