Preheat your oven to 350°F (175°C) to ensure even baking.
Cream the softened butter and granulated sugar in a large mixing bowl using an electric mixer until light and fluffy, about 3-5 minutes.
Add the room temperature eggs one at a time, mixing well after each addition. Then add the vanilla extract and blend until incorporated.
In a separate bowl, whisk together the all-purpose flour, baking powder, and kosher salt. Gradually add this dry mixture to the wet ingredients, mixing just until combined.
Using a cookie scoop or tablespoon, portion out the dough onto lined baking sheets, spacing them about 2 inches apart.
Bake in the preheated oven for 8-10 minutes, or until the edges are lightly golden. The centers will look slightly underbaked.
Allow the cookies to cool on the baking sheets for about 5 minutes before transferring them to a wire rack to cool completely.
Beat the softened butter for the frosting until creamy. Gradually add the sifted confectioners sugar, mixing on low. Then add the vanilla bean paste and half and half, beating until fluffy.
Once the cookies are completely cool, spread frosting on each cookie and sprinkle with colorful sprinkles if desired.
