Preheat your oven to 350°F (175°C). Grease a 9-inch cake pan with butter and dust it with flour.
In a medium bowl, sift together the flour, baking powder, baking soda, and salt.
In a large mixing bowl, beat the butter until it’s light and fluffy. Add in the sugar and beat until well combined.
Add in the eggs, one at a time, beating well after each addition. Stir in the vanilla extract.
Gradually add in the flour mixture to the butter mixture, alternating with the buttermilk. Begin and end with the flour mixture, mixing until just combined after each addition.
Pour the batter into the prepared pan and smooth the top with a spatula.
Bake for 40-45 minutes or until a toothpick inserted in the center comes out clean.
Remove the cake from the oven and let it cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.