Preheat your oven to 350°F (175°C). Grease and flour a 9-inch round cake pan.
In a mixing bowl, cream together the butter and sugar until light and fluffy. Add the eggs one at a time, beating well after each addition. Stir in the vanilla extract.
In another bowl, whisk together the flour, baking powder, and salt. Gradually add the dry ingredients to the butter mixture, alternating with the milk, beginning and ending with the dry ingredients. Mix until just combined.
Pour the batter into the prepared cake pan. Bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean. Allow the cake to cool completely.
For the lemon cream filling, whip the heavy cream until stiff peaks form. Gently fold in the lemon curd until well combined.
Once the cake is cool, slice it in half horizontally. Spread the lemon cream filling on the bottom half, then place the top half back on. Dust with powdered sugar before serving.