Line the cupcake tins with paper liners. Preheat oven to 350 degrees.
Mix the flour, sugar, cocoa, baking soda, baking powder, and salt in a bowl.
In a separate bowl add the eggs, whole milk, oil, and vanilla.
Add the bowl containing the eggs, whole milk, oil, and vanilla to the bowl holding the dry ingredients.
Mix all together until fully incorporated.
Beat for 3 minutes on medium.
Slowly add the boiling water starting with a small amount then pour in the remaining boiling water.
The batter may be a little runny.
Scoop batter into cupcake lined cups until 3/4s filled.
Bake at 350 degrees for 20-25 minutes.
Remove from oven and allow to cool for 10 minutes.
Take out of the cupcake pan placing on a wire rack until completely cooled.
Cream the butter and powder sugar until it looks light and creamy.
If it doesn't cream add several drops of the heavy whipping cream until it creams.
Test to see if the frosting can form and hold a stiff peak by taking a spoonful of frosting and turning the spoon upside down. If the frosting stays on the spoon it is ready if not then.... Add more powder sugar 1/2 C at a time.... mix well.
If ready scoop the frosting into a pastry bag with a large tip.
Twist the open end of the pastry bag to push the frosting to the tip.
Start the frosting on the outside edge of the cupcake working to the center of the cupcake.
Place the separated Oreo as ears on the top of the frosted cupcakes.
Place the two M & M's on the upper part of the cupcake as eyes.
Use a #48 pipping tip, also called the basket weave tip, to create the mummy wraps.