1) Preheat oven to 350 degrees Fahrenheit. In a bowl add all dry ingredients, mix together and then add wet ingredients. Mix well and pour into a 9" greased cake pan. Bake for 20 to 25 minutes. Check with a toothpick or knife to see if it is done.
I topped mine with a simple vanilla frosting and added some grapefruit juice to it. This cake is delicious and can be dusted with sugar if you want.
Enjoy!
Source of recipe: I couldn't find any good grapefruit cake recipes so I made this one up.