Fran’s Herman cake

Just to be clear: this was Fran’s project. But as I’m enjoying eating it, she’s given me permission to cover it.

For those who’ve never encountered it, Herman cake, or friendship cake, is a type of apple cake that features a starter not unlike a sourdough. The principle is that you feed up the starter, then split it and pass containers of sludge onto your friends for them to then follow the recipe, and in turn pass sludge onto their friends.

Fran was given it by our friend Martina, another parent at our kids’ school. Seeing as I’m the avid baker of the household, I’m somewhat bemused she didn’t offer it to me. But as I was in thick of home-schooling our five year old and seven year old at that point, nurturing a pot of seething yeasts and lactobacilli as well was possibly a bridge too far for me.

The Herman cake starter isn’t strictly a sourdough. Or not necessarily. I’ve seen recipes online where people create the starter not by awaiting the gentle cascade of natural yeasts from the atmosphere but by making a batter with flour, milk, sugar, water and commercial yeast. Over time, however, this mix is fed (with more flour and sugar) and will take on naturally occurring yeasts and bacteria, and will give off that beery smell familiar to those who cultivate stricter natural leavens.

This type of cake is inspired by an older Amish tradition, Amish friendship bread, which itself would have originally used a true natural sourdough starter. Indeed, all breads and leavened baked goods did before the controlled cultivation and commercial sale of baker’s yeast, Saccharomyces cerevisiae, in the second half of the 19th century following the Louis Pasteur’s advances in the understanding of microbiology.

A few notes:
1. Don’t refrigerate the starter. Just keep the sludge in a bowl, covered loosely with a clean cloth, at room temperature.
2. The final cake ingredients do include baking powder, which seems odd considering you’re using a sourdough-like starter – ie a leaven. But the result is delicious, so I’m not quibbling.
3. The recipe suggests cooking apples, but Fran used desert apples and they worked well. (Gala I believe.)
4. The original recipe also included raisins, but cooked raisins are a sure way to ruin a cake. They’re the devil’s work, like sultanas in the curries we used to have at primary school in the 1970s. Of course, if you like dried fruits in cakes, go ahead and add some.
5. You can add a streusel topping. My mum used to make us a streusel cake when I was a kid, so I’ve taken that element from her old Katie Stewart recipe.
6. It’s quite a big cake. Fran made it in a 23x23cm square tin. I can’t see any reason why you can’t bake it in a round tin, bundt tin or deep roasting pan, depending on what you’ve got at your disposal.
7. I would love to know how the microbiology of a Herman starter differs from that of a classic sourdough (which of course varies a lot too). There is a Herman Project underway looking at the microbial characteristics of different sourdoughs. It’s discussed here, but the link from this MIT page is dead, so I don’t know if it looks at these cake starters.
8. When Fran divided up the Herman starter, each quarter weighed around 300g.
9. I’ve no idea why it’s called Herman. Apparently, “Herman” is an affectionate name for any sourdough starter, though I’ve not heard that before. Presumably in America. Though again, I’ve no idea why that particular name was chosen.

So, assuming a friend passes you a container of sludge, here’s the recipe.

Starter
1. The day you receive the sludge is day 1. Stir each day and on day 4 add 140g plain flour, 200g caster sugar and 225g of full-fat milk.
2. Stir each day on days 5 to 9, then add 140g plain flour, 200g caster sugar and 225g of full-fat milk on day 9.
3. Weigh the mixture then divide into four equal portions. Give three containers of sludge away to friends.
4. Keep your quarter for one more day, then you’re ready to make the cake on day 10.

Cake ingredients

300g Herman starter
225g caster sugar
300g plain flour
12g baking powder
3g fine sea salt
155g cooking oil (sunflower or vegetable [ie rapeseed, aka canola] good)
2 medium eggs (ie around 115g, without shells)
10g vanilla essence
2 medium apples, cut into chunks
12g ground cinnamon

Optional streusel topping
50g self-raising flour
100g soft brown sugar
50g butter, melted

1. Grease a 23cm square tin and line with baking parchment.
2. Preheat your oven to 170C.

3. Simply combine all the ingredients and pour into the prepared tin.
4. To make the optional streusel, combine the flour and sugar in a small bowl and mix through the melted butter with a fork. Sprinkle this onto the cake batter.
5. Bake for around an hour, until a skewer comes out clean (-ish). If it’s not baked enough but the top is browning, cover with foil and keep baking.
6. Cool on a wire rack.
7. Enjoy. Or not if you’re a five year old who refuses to eat the cooked apple.