1. Once the challahs are completely cool, transfer them to a wire cooling rack with a piece of parchment paper underneath to catch all the excess icing.
2. Whisk together the confectioners’ sugar and non-dairy milk until combined. Pour icing over the challah and immediately decorate with sprinkles before it hardens.
3. Repeat with the second challah. If you’re running out of icing, use the extra icing that pooled underneath the cooling rack. Decorate the second challah and allow it to harden. Slice and enjoy!!