May 14, 2018
Walnut slices are rich, quite sweet cakes that cannot be found in any Slovenian cook book, yet appear at pretty much every big countryside event, such as weddings, and have been circulating around for several generations, mostly orally, then also through cooking pen clubs, from mothers to daughters, and most recently through internet forums.
Walnut slices bare many names, including London slices, Zagreb slices, crunchy walnut slices and, in one of the online arguments about the “correct” term, it has been suggested that in the version in which walnuts are replaced with coconut flour we get what should be called Berlin slices. This indicates that the name itself could be misleading or has little to tell us about their origin, although we could conclude on the origin of the person naming them, i.e. someone calling them Zagreb slices is possibly from Maribor, while someone calling them London slices is probably from Ljubljana or Belgrade.
Walnut slices are in fact as popular in Slovenia as in Serbia, suggesting their origin is somewhere in the south instead of the north, let alone London. They might have evolved as a cross-breed of pie and macaroons, with the latter first appearing in an Italian monastery in the 9th century and are brought from there to the French court six centuries later. That is, from south to the north again.
So far, they might as well be called Yugo slices, if we hadn’t found one recipe which resembles Berlin slices under the title Alexa Johnston reintroduces an innovative tin-filler from 1950s New Zealand (ginger meringue bars). So the recipe might originate from some global experimental craze from the fifties. Nevertheless, it grew firmly into Slovenian cultural fabric, which gives us freedom to consider it part of traditional Slovenian cooking now. After all, tomatoes, the core ingredient of Italian cuisine, are from the New Wold, so is the chilli, the core ingredient of Sichuan food, and it was Norwegians who put salmon on sushi first, which nevertheless makes it no less Japanese. Which is why we can claim that London slices are in fact a traditional Slovenian cake that we happen to share with other cuisines in the region, Serbian in particular.
Most importantly, this mysterious cake is delicious and surprisingly easy to make.
300g sharp (ostra) white flour
5 egg yolks
200g apricot marmalade (better sour than sweet)
5 egg whites
200g ground walnuts
Make the dough: mix sugar with butter, add egg yolks and finally flour.
Preheat oven to 180 degrees.
Butter and flour your baking try and place the rolled dough in it. If the dough keeps breaking like ours did, and if your pan allows it, just roll the dough inside the cake pan, then press with your fingers against the rims and remove the excess dough.
Now put the dough into the preheated oven to bake at 180 degrees Celsius for about 10 minutes.
Meanwhile beat the egg yolks, slowly add sugar when soft peaks start to form and hope it will not completely collapse after all the sugar is in. Ours did, so we had to beat it for another 7 minutes to get it a bit fluffier, but failed at achieving the full hardness that would allow it to support its own shape, which is OK, as no shape is required to be supported anyway. We then slowly stir in 200 grams of walnuts.
Don’t forget your dough in the oven. Take it out and spread the apricot marmalade on top. Opt for sour versions with more fruit content. In case your marmalade is full of chunks of fruit, smooth it first in a blender.
Spread the walnut-meringue mixture over the marmalade. Don’t stir the marmalade in when spreading the meringue, make sure it just covers it instead.
The pie is now ready to be placed in the oven for another 10 minutes.
The meringue will break less if cut while still hot.
Serve them when they are cooled.
Walnut slices have to be kept in an air-tight box to preserve the moisture and can last for quite a few days, although good luck keeping any uneaten after a few hours.