Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
In a medium bowl, whisk together the flour, baking powder, and salt. In a large bowl, cream the butter and sugar until light and fluffy. Beat in the eggs one at a time, then stir in the vanilla.
Add the dry ingredients to the wet ingredients alternately with the milk, mixing just until combined. Pour the batter evenly into the prepared cake pans.
Bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean. Allow the cakes to cool in the pans for 10 minutes, then transfer them to a wire rack to cool completely before frosting and decorating.
When decorating the cake, feel free to get creative with frosting, sprinkles, candles, and other festive embellishments.
Consider adding a personal touch, such as writing the celebrant's name or a special message on the cake. Remember to have fun and enjoy the process of creating a beautiful and delicious birthday treat.