Preheat oven to 350°F (175°C) and grease a 9-inch cake pan.

In a large bowl, cream butter and sugar until light and fluffy.

Beat in eggs one at a time, then mix in vanilla extract.

In a separate bowl, whisk together flour, baking powder, and salt.

Gradually add dry ingredients to the wet mixture, alternating with milk.

Pour batter into prepared cake pan and bake for 30–35 minutes, until a toothpick comes out clean.

Let cool for 10 minutes before transferring to a wire rack.