OK, this is not a very successful attempt. The recipe I was using was WRONG. It said very clearly to prepare TWO swiss roll tins, then it had you make the batter and put it into the pan. Singular–pan. I missed that little detail but never did figure out what the second tin was for! So, I cooked two thin pieces of cake.
I made the strawberry jam using regular sugar instead of “jam sugar”, which I had never heard of before. Turns out it’s sugar with pectin already mixed in. Luckily, I had some pectin laying about, so I added half the packet and it thickened up nicely.
The butter cream frosting that you put in the middle is a bit thick using the list of ingredients. I’d probably add just a spoonful more milk to thin it out…or just use something else because it was sickeningly sweet. Maybe a nice thick custard or thick whipped topping?
Anyway, just to keep things simple, I’m posting this moderate success.