1. In a large mixing bowl, cream together the butter and sugar until light and fluffy.
2. Add the vanilla extract and eggs, one at a time, beating well after each addition.
3. In a separate bowl, whisk together the flour, baking powder, and salt.
4. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
5. Fold in the sprinkles.
6. Divide the dough in half and shape each half into a log about 2 inches in diameter. Wrap in plastic wrap and refrigerate for at least 1 hour.
7. Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper.
8. Slice the dough into ¼-inch thick rounds and place them on the prepared baking sheet.
9. Bake for 10-12 minutes, or until the edges are lightly golden. Cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely.