For the best texture, use finely ground blanched almond flour rather than coarse almond meal, which can make the cookies gritty and more fragile. Chilling the dough is essential because it allows the butter to firm up, helping the snowball cookies hold their round shape instead of spreading into flat discs. To keep the coating smooth and snowy, always use powdered sweetener and avoid granulated varieties, which will not melt into the surface of the cookies. These cookies freeze well after baking; freeze in a single layer until solid, then transfer to an airtight container with parchment between layers and add a fresh coating of powdered sweetener after thawing.