1. Preheat oven to 350°F (175°C) and line an 8×8-inch pan with parchment paper, leaving an overhang.

2. In a medium bowl, whisk together flour and powdered sugar, then cut in the cold butter until the mixture resembles coarse crumbs.

3. Press the crust mixture firmly into the bottom of the prepared pan and bake for 18-20 minutes until lightly golden.

4. While the crust bakes, whisk together granulated sugar and flour, then add eggs, lemon juice, and zest, mixing until smooth.

5. Pour the lemon filling evenly over the hot crust and return to the oven to bake for 20-25 minutes, until the center is just set.

6. Cool the bars in the pan for one hour at room temperature, then refrigerate for at least 2 hours until completely firm.

7. Lift the bars from the pan using the parchment, cut into squares, and decorate with candy eyeballs and an orange sprinkle beak.