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

In a large mixing bowl, cream together the softened unsalted butter and granulated sugar until light and fluffy.

Add the eggs one at a time, beating well after each addition.

Pour in the pure vanilla extract and mix on low speed until combined.

In a separate bowl, whisk together the all-purpose flour, baking powder, and salt. Gradually add to the wet mixture.

Pour in the whole milk or heavy cream and mix until smooth.

Transfer the batter to the prepared pan and smooth the top.

Bake for 40-50 minutes until golden brown and a toothpick comes out clean.

Allow to cool in the pan for 10-15 minutes, then transfer to a wire rack to cool completely.