islamic new year cooking

[Yuki Nomose]

i knew that it's considered bidah every cooking dishes for muharram but i have seen people that make this and my husband relatives ( pashto ) invited me to eat with them and i'm become a bit confused. Off course i have readed everywhere that its FORBIDDEN this but in pravacy houses it seems not many respected especially families with children ^o)

offcourse my husband is not shia but it seems shia tradition or not on cooking during muharram????