In a medium bowl, combine together flour and salt and mix.
In a separate bowl, using electric mixer, beat softened butter and granulated sugar until light in color and fluffy. Add an egg and vanilla – continue beating for a couple minutes. Turn off the electric mixer, add flour-salt mixture and then continue beating on low speed until well-combined but without over mixing.
ll dough into 1-inch balls. Roll these cookie balls in sprinkles. Arrange on parchment-lined baking sheets, spacing 2 inches apart. Freeze until firm, for about 30 minutes.
Bake at 350 degrees F in the preheated oven for 14 minutes. Do not over-bake. Remove from the oven, and transfer to wire rack to cool completely.