Add sugar on top, then baking powder, then salt. Place lid on jar. (My ingredients JUST fit)
When Ready to Prepare Cake Batter
Place softened butter into stand mixer and mix on medium for 1-2 minutes.
Place dry ingredients into stand mixer and combine with butter for 30 seconds.
Add milk, oil, vanilla and eggs and mix on medium-high for one minute.
Pour batter into prepared pans. Bake at 350°F. For 8-inch pans it's 20-25 minutes. For cupcakes start checking around 15 minutes. To make in a 9x13, bake for 30-38 minutes. Cool before frosting.