Preheat the oven to 350°F. Line cupcake pans with liners.
In a medium bowl, sift together the flour, baking powder and baking soda; set aside.
In another bowl, combine the hot water or coffee and cocoa; set aside.
In a large bowl, use an electric mixer to cream together the sugar, butter, salt and vanilla. Add the eggs, one at a time, and continue creaming until light and fluffy. Mix in the applesauce.
Add the dry ingredients and the buttermilk alternately to the wet ingredients. Then add the hot water mixture and mix until thoroughly combined.
Scoop the batter into cupcake pans and bake for 15 to 20 minutes, or until a toothpick inserted into the center comes out clean. Let the cupcakes cool completely before adding ganache.
MAKE THE GANACHE:
In a medium glass bowl (or small saucepan), bring cream and sugar just to a boil (in the microwave or on the stove). Then remove from heat and add the chocolate. Let it sit for about 1 minute, then whisk together until smooth. Then stir in the butter until melted.
Dip the tops of the cupcakes into the warm ganache. Set on a cooling rack to dry. When the remaining ganache sits for a while (or refrigerate for a few minutes), it will get thicker. At this point, you can spoon it into a piping bag and then pipe more ganache on top for decoration.