That is just so, so adorable! On mossandstonegardens.com, they sell little smooth rocks with a thumbprint style impression in the center of the top, with moss growing in it. Because moss doesn’t have roots, it does not need to be ‘potted’. Just mist it often. I think it’s a bryophyte. I like this ‘spoonful of nature’ and cute little cottage. It looks teensy & cheerful. Thanks!