If a recipe requires, say, 500g of potatoes, peeled and sliced...

[JenaiMarrHePlaysGuitar]

Do they mean 500g of peeled potatoes or 500g of potatoes, peeled?

Ahem. Do I weigh out 500g of potatoes and peel them, or do I need 500g of peeled potatoes?

I'd weigh it peeled not unpeeled but I don't know if that's right!

I think you are overthinking this

get 500g of spuds and peel 'em

It's 500g of spuds as the amount and then 'Peel and slice' them as the instruction.

I think they mean peeled weight, but I can't imagine actaully weighing them. Just enough so it looks about right

Lol yes, overthinking!
Am making fishcakes from a rather old Richard Stein book (from before he was "Rick").

Definately potatoes unpeeled, then the method would say to peel them

In which he talks about how we shouldn't overlook cheap fish, such as cod