Preheat oven to 350°F (175°C).
In a large bowl, mix the flour, baking powder, and salt. Set aside.
Cream together the sugar and softened butter until light and fluffy. Add the eggs and lemon extract, and beat well until combined.
Gradually add the flour mixture to the wet ingredients, mixing until smooth. The dough will be slightly sticky. If desired, add a drop or two of yellow food coloring for a vibrant look. Chill the dough until firm.
Using a small cookie scoop, drop rounded spoonfuls of dough onto a lightly greased cookie sheet, spacing them about 2 inches apart.
Bake for 12-15 minutes, or until the cookies are firm and lightly golden. Remove from the oven and allow them to cool completely.
To make the glaze, combine the confectioners' sugar, water, and lemon extract in a bowl. Mix until smooth. The glaze should be thick but still runny enough to coat the cookies.
Dip the tops of the cooled cookies into the glaze, then place them on a wire rack, allowing the glaze to drip down the sides.
While the glaze is still wet, top with sprinkles or a little lemon zest for decoration.
Store the cookies in an airtight container. If freezing, freeze unfrosted cookies and glaze after thawing.