Preheat your oven to 350°F (175°C).

Grease your 9-inch round baking dish with butter or non-stick spray.

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

In another bowl, cream the softened butter and sugar until light and fluffy.

Beat in the eggs one at a time, then stir in the milk and vanilla extract.

Gradually add the dry ingredients to the wet mixture, stirring gently until just combined.

Pour the batter into the prepared baking dish, smoothing the top with a spatula.

Bake in the preheated oven for 30 to 40 minutes, or until a toothpick comes out clean.

Let the cake cool in the pan for about 10 minutes before transferring it to a wire rack.