01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - Whisk flour, baking soda, salt, cinnamon, and nutmeg together in a medium bowl. Set aside.
03 - Using an electric mixer, cream softened butter with granulated sugar on medium speed until light and fluffy, about 2–3 minutes.
04 - Beat in egg, lemon juice, lemon zest, and vanilla extract until fully incorporated.
05 - Gradually add dry ingredients to wet mixture, mixing on low speed until just combined. Do not overmix.
06 - Scoop tablespoon portions of dough onto prepared baking sheets, leaving 2 inches between each mound.
07 - Bake for 10–12 minutes until edges are lightly golden. Remove from oven and cool cookies on baking sheets for 5 minutes.
08 - Transfer cookies to a wire rack and allow them to cool completely before glazing.
09 - Whisk powdered sugar, lemon juice, and milk in a small bowl until glaze is smooth and pourable.
10 - Drizzle or spread glaze over fully cooled cookies. Immediately apply sprinkles if desired.
11 - Allow glaze to set completely before serving or storing cookies.