Step 1: Preheat your oven to 350°F (175°C). Grease and flour a 9-inch round cake pan or line it with parchment paper.
Step 2: In a large mixing bowl, cream together the softened butter and granulated sugar until the mixture is light and fluffy, about 3-5 minutes.
Step 3: Add the eggs one at a time, beating well after each addition to ensure they are fully incorporated. Stir in the vanilla extract.
Step 4: In a medium bowl, whisk together the all-purpose flour, baking powder, and salt.
Step 5: Gradually add the dry ingredients to the creamed butter mixture, alternating with the milk. Start and end with the flour, mixing only until just combined.
Step 6: Pour the batter into the prepared cake pan and smooth the top with a spatula.
Step 7: Bake for 30 to 35 minutes, or until the cake is golden brown and a wooden skewer inserted into the center comes out clean.
Step 8: Allow the cake to cool in the pan for 10 minutes, then transfer it to a wire rack to cool completely.
Step 9: Once cooled, dust the top generously with confectioner's sugar before slicing and serving.