Mix well and pour into a 9 x 13 cake pan that has been greased and floured.
Wrap the pan with insulated cake pan strips>>>you can buy them at wal mart. I personally just ripped up an old thick towel.
Tear into strips about 2-3″ wide. Make a strip long enough to fit around any pan you use. If you need to piece it together to make it fit, use sewing pins (straight pins).
Soak the strip with cold water and wring it out a little…wrap your pan with it.
The strips keep the pan edges from heating up too fast and will allow the cake to rise evenly all the way out to the edges of the pan…no more hard edges on your cakes
Bake for the time recommended on the box, until toothpick inserted in center of cake comes out clean
Let cool completely before you frost.