Heat the oven to 350 degrees and line a baking sheet with parchment paper.
In a mixing bowl, beat the softened butter and granulated sugar until smooth. Add the maple syrup and egg yolk and mix until combined.
Stir in the flour, baking powder, and salt until a soft dough forms. Divide the dough into 8 equal pieces and roll each into a ball. Place the balls on the prepared sheet and flatten slightly with your palm.
Bake for 10 to 12 minutes until the edges turn lightly golden. Remove from the oven and let the cookies cool completely on the sheet.
While the cookies cool, whisk the powdered sugar, milk, and vanilla extract in a small bowl until the mixture reaches a thick but pipeable consistency.
Transfer the icing to a piping bag fitted with a small round tip. Pipe horizontal strips across each cookie to resemble mummy bandages, leaving space for the candy eyes.
Press two candy eyes onto each cookie while the icing is still soft. Let the icing set for 20 minutes before serving.