01 - Preheat oven to 350°F and line two baking sheets with parchment paper.
02 - Whisk flour, baking soda, salt, cinnamon, and nutmeg in a medium bowl; set aside.
03 - Beat softened butter with granulated sugar until light and fluffy, about 2 to 3 minutes, using an electric mixer.
04 - Blend in egg, lemon juice, lemon zest, and vanilla extract to the butter mixture until fully combined.
05 - Gradually add the dry ingredient mixture to the wet ingredients, mixing just until combined.
06 - Scoop tablespoon-sized portions of dough onto prepared baking sheets, spacing each piece about 2 inches apart.
07 - Bake for 10 to 12 minutes, or until edges are lightly golden. Allow cookies to cool on baking sheet for 5 minutes, then transfer them to a wire rack.
08 - Whisk powdered sugar, lemon juice, and milk together in a bowl until smooth and pourable.
09 - Once cookies are cooled, drizzle or spread glaze over each one, adding sprinkles or edible glitter immediately if desired.
10 - Allow glaze to set fully before serving or storing cookies in an airtight container.