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 25-30 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.