Preheat your oven to 350°F (175°C) and line a large baking sheet with parchment paper.
In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until the mixture is light and fluffy, about 3 minutes.
Beat in the egg and vanilla extract until fully incorporated, scraping down the sides of the bowl with a spatula.
In a separate small bowl, whisk together the flour, baking soda, and salt.
Gradually add the dry ingredients to the wet mixture, mixing on low speed until just combined. Fold in 1/4 cup of the sprinkles by hand.
Scoop rounded tablespoons of dough, roll them into balls, and then roll each ball in the remaining sprinkles until coated.
Place the dough balls on the prepared baking sheet, spacing them about 2 inches apart.
Bake for 9 to 11 minutes or until the edges are just set and the centers look slightly soft.
Remove the baking sheet from the oven and immediately press one unwrapped chocolate kiss into the center of each warm cookie.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.