Mix butter with an electric mixer until very soft and creamy.
1 cup butter
Mix in sugar until light and fluffy.
1 ½ cups sugar
Add egg and vanilla. Mix well
2 teaspoons vanilla, 1 egg
Add flour, baking powder and salt. Mix until the dough is crumbly. The dough will look dry, but will come together when pressed.
3 ¼ cups flour, ½ teaspoon baking powder, ¼ teaspoon salt
Dump dough onto a flat surface. Divide into two piles. Working with one section at a time,form dough into a 10 inch log. The dough will begin to stick together when pressed. If it breaks apart, simply press back together.
Pour ¼ cup of sprinkles onto a rimmed baking sheet. Roll logs into sprinkles.
½ cup colored sprinkles
Place each log on a sheet of plastic wrap. Divide remaining sprinkles between each log. Pour sprinkles over each log. Wrap each log fully with plastic wrap. Use your hands over the plastic wrap to smooth sprinkles into logs.
Refrigerate for at least one hour.
Remove plastic wrap and cut into ½ inch slices. Place on a baking sheet lined with parchment paper or grease baking sheet lightly.
Bake in a preheated 375 degree oven for 12-14 minutes.
Let cookies cool slightly on baking sheet. Remove and continue cooling on baking rack.