It's not custard, it's not a cross between pudding and custard.
It is pudding, American style. Lots of cornstarch.
(Like Jello Pudding, American pudding... not British pudding because I'll never be able to understand their use of the word. Spotted dick is pudding? Yorkshire pudding? What? I might as well learn the rules of cricket.)
I must emphasize this because I've met too many people that find themselves unable to describe Vla except that it is special and delicious, saying, "It is not pudding, it's more like a sort of custard."
Well, it IS pudding. And it comes in a carton.
The carton looks like this because it is impossible to empty it without squeezing, shaking and questioning the rationale for selling it in a carton.
In fact, when I read about Vla on Wikipedia it led me to the entry on the flessenlikker.
Bottlelicker! We have one! We couldn't find a spatula so we bought this weird little plastic thingy that apparently has a unique Dutch background.
"It is a common tool in kitchens in the Netherlands and available in many kitchen stores and supermarkets — although this may vary by region. It is almost wholly unused and unknown outside of that country."
Indeed. Thank Vla for the flessenlikker. Now where can I buy my pudding in a bottle?