Beat the butter & sugar until fluffy.
Beat in the egg & extract.
Add the flour & salt to the butter mixture.
Shape the dough into 1-inch balls; roll in the sprinkles.
Place the rolled cookies on a paper plate & flatten each slightly with the bottom of a glass.
Top with a pinch of additional sprinkles.
Freeze until firm, approximately 15 minutes.
Preheat the oven to 350° & line the baking sheets with parchment paper.
Remove the cookies from the freezer & place at least 2 inches apart on the prepared pans.
Bake until the edges are lightly browned.
Let cool on the pans for at least 2 minutes.
Remove from the pans, & let cool completely on a wire rack.