Step 1: Preheat your oven to 350°F (175°C) and line a 9×13 inch baking pan with parchment paper, leaving an overhang on the sides for easy removal.
Step 2: In a large bowl, cream together the softened butter and granulated sugar until the mixture is light, fluffy, and pale in color.
Step 3: Beat in the eggs one at a time, then stir in the vanilla and almond extracts until well combined for the skeleton sugar cookie bars recipe base.
Step 4: In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Step 5: Press the dough evenly into the prepared baking pan using a spatula or clean hands to ensure a level surface.
Step 6: Bake for 20-25 minutes, or until the edges are barely golden. Do not overbake! Allow the bars to cool completely in the pan before lifting them out.
Step 7: Cut into rectangles. Use the white royal icing to pipe a skull and bone structure on each bar, then use the black icing to add facial details to your skeleton sugar cookie bars recipe.