Preheat the oven to 350°F. Grease and line with parchment paper one 9x13-inch pan or two 9-inch round cake pans.
Combine flour, salt and baking powder, set aside. Cream together butter and sugar until light and fluffy, about 10 minutes. Add eggs one at a time, beating well after each. Add milk and vanilla, alternating with the flour mixture, and beat until smooth.
Pour into the prepared pans and bake for 25 to 30 minutes or until inserted toothpick comes out clean.
Let cool for 15 minutes in cake pan. Remove cake and cool completely on wire rack before frosting.