Gather all ingredients and allow butter, eggs, and milk to come to room temperature (this is crucial for a smooth batter).

Preheat your oven to 350°F (175°C). Grease and flour a 9x13-inch baking pan, or line with parchment paper for easier removal.

In a medium bowl, whisk together the flour, baking powder, and salt. Set aside.

In a large mixing bowl, cream together the softened butter and sugar until light and fluffy, about 3-4 minutes. This incorporates air into the batter for a lighter texture.

Add eggs one at a time, beating well after each addition. Scrape down the sides of the bowl as needed.

Stir in the vanilla extract.

Gradually add the flour mixture to the butter mixture, alternating with the milk, beginning and ending with the flour (flour-milk-flour-milk-flour). Mix just until combined after each addition. Be careful not to overmix.

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

Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted in the center comes out clean or with a few moist crumbs.

Allow the cake to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before frosting.