Police are investigating the culinary mix-up that led to the cannabis-infused confection being served at the restaurant hosting a funeral party after a burial.

Officers in Rostock, in eastern Germany, said one of the restaurant workers had asked her 18-year-old daughter to bake cakes for the occasion.

However, a mix-up led to the mother taking the hash cake the teenager allegedly made for another occasion instead of the funeral cakes.

The 18-year-old is now under investigation, The Guardian reports.