This is my best shot at imitating my favorite cupcake at the Cocoa Bean Cupcake Cafe and I think I came pretty close.  YUM!  I found this recipe for Wacky cake out of the 2008 classy cookbook and it has been a favorite ever since.  
Wacky Cake
3c flour
2c sugar 
6 Tbsp baking cocoa
1 teaspoon salt
2 Tsp baking soda
Mix dry ingredients well and add:  2 tbs vinegar, 3/4 cup vegetable oil, 2 cups cold water, 2 tsp vanilla.  Mix together well.  Bake at 350 for 25-30 min for 9  by 13 and 15 to 18 min. for cupcakes.  This is a great moist cake and if your husband happens to be allergic to eggs it's even better.
Vanilla Buttercream Frosting
3 cups powdered sugar
1/3 cup butter, softened
1 1/2 tsp vanilla
1 to 2 tbs milk
Mix powdered sugar and butter, stir in vanilla and milk.  Gradually beat in enough milk to make it smooth and spreadable. 
 For frosting cupcakes I usually put mine in a gallon plastic bag and snip the corner off and pipe it on. Sprinkle with crushed Heath Candy Bar