Combine the butter and sugar in the bowl of a stand mixer on medium speed until smooth and fully combined.
Add the egg and vanilla to the bowl of the stand mixer and blend another minute or so to fully incorporate.
Add the cinnamon and baking powder to the mixture and blend until combined.
Slowly add the flour to the bowl of the stand mixer and blend until just combined.
Turn the cookie dough out onto a powdered sugar-dusted surface and roll to around 1 to 1½ inch thickness.
Use the Santa's glove cookie cutter to cut cookies and place each of them on a parchment paper-lined baking sheet.
Bake the cookies for about 7 to 9 minutes or until they start to brown slightly around the edges.
Let the cookies cool for 5 minutes on the pan and then move to a cooling rack to cool completely before decorating.
Once the cookies have cooled completely add a layer of white royal icing to each one to start the decoration. Let this layer dry completely before moving to the next step.
Use a piece of parchment paper to cover over the "thumb" of each cookie and spray the glove part using a grey spray on icing color. Allow this layer to dry completely before moving to the next step.
Use a black decorating gel to add the RIP to each of your grey tombstones. You can also use the decorating gel to add two eyes (and a little mouth if you like) to each of the ghosts that are now popping out from behind the tombstones. Let this layer of decoration dry completely before moving on to the next step.
Uses green decorator icing to add grass to the bottom of each tombstone.