Preheat the oven to 375° Fahrenheit.
In a stand mixer, combine the softened butter and sugar. Starting on low, cream together the butter and sugar for about 3 minutes. Add in the egg and mix for about 30 seconds, then add in the vanilla extract, and mix for another 30 seconds.
In a separate mixing bowl stir together the flour, baking soda, and salt.
Add the dry ingredients into the wet ingredients. Starting on low, gently increase the speed of the stand mixer, until the wet and dry ingredients are just combined.
Fold in the sprinkles. Use a 1/4 teaspoon to scoop out dollops of cookie dough. Roll the cookie dough into balls and place about 12 of them on the cookie sheet. Bake for 8-10 minutes, until the cookies are slightly golden.
Remove the cookies from the oven and let cool for 10 minutes. Use a spatula to remove the cookies from the cookie sheet. Transfer them to a cooling rack and let them cool. Then enjoy!
Store in an airtight container for up to a week, for optimal freshness.