Preheat oven to 350F. Line two baking sheets with parchment paper. Set aside.
In a medium bowl, whisk together the flour, baking soda, baking powder and salt.
In the bowl of a stand mixer fitted with the paddle attachment, beat the butter, granulated sugar and brown sugar and beat until light and fluffy, 3 minutes.
Scrape the bottom and sides of the bowl with a spatula.
Beat in the egg, egg yolk, vanilla and mix until well combined.
Add the dry ingredients and mix on low until just combined. The dough will be thick.
Beat in the sprinkles until just mixed.
Place the 1/3 cup of sugar into a bowl. Using a 2 tablespoon ice cream scoop, scoop out the dough and form into balls.
Roll the dough balls in the sugar to coat.
Place two inches apart on the cookies sheets. Bake for 10-12 minutes, until the edges start to turn a light brown and the top begins to crack.
Let the cookies cool on the baking sheet for 5 minutes before transferring to a cooling rack to cool completely.