Preheat the oven to 350℉
Cream butter, sourdough discard, powdered sugar, and vanilla extract on low/medium speed until light and fluffy.
Wisk together the flour and salt then add to your wet ingredients
Mix on low speed, until just combined. Use a rubber spatula to scrape the sides of the bowl to incorporate all the dry ingredients.
Your dough will be a bit crumbly after using a mixer, but begin to bring it all together with your hands once mixed and you will have a nice dough ball that is no longer crumbly.
Use a cookie scoop or tablespoon measuring spoon to scoop the cookie dough and roll it into a cookie dough ball with your hands.
Line a cookie sheet with parchment paper.
Place dough balls on the prepared baking sheet and place in a heated oven
Bake cookies at 350℉ for 20-22 minutes. I typically pull mine out at 21 minutes.
Let cookies cool for just a minute so they aren't too hot. Then, gently roll the warm cookies into a bowl of confectioners' sugar and cool on a separate platter or cooling rack. The powdered sugar will melt a little as the cookie is still warm, but it will help it stick better. Once cooled down, roll your snowballs for a final coat.