In a large bowl, beat butter and powdered sugar until light and fluffy. Mix in egg, vanilla, and almond extract.

In a separate bowl, whisk flour, baking powder, and salt. Gradually add to the butter mixture until a dough forms.

Divide dough into 2 portions, wrap in plastic, and chill for 30 minutes.

Preheat oven to 350°F (175°C). Line baking sheets with parchment paper.

Working with small pieces of dough, roll into thin finger-shaped logs. Pinch in a few spots to form 'knuckles' and use a knife to lightly score wrinkles.

Press a whole almond at one end to make the fingernail. If desired, dab underneath with red gel or jam for a bloody look.

Place cookies on baking sheet and bake for 12–15 minutes, until lightly golden around the edges.

Cool completely. Add extra jam or red gel around the 'nail bed' for a creepier finish.