I wanted to finish this series with another cake – a bit of an occasion cake that you could make for a birthday or dinner party. The obvious choice is a Victoria sponge, which you can make plain or chocolate, and fill with buttercream. But to be honest, you just need to follow the cupcakes recipe from this series, double it and bake it in two 20cm sandwich tins. Very easy.

Instead, I wanted to explore one of the best things about baking – experimenting.

Experimenting with food

One of the joys of baking is that you can play around and invent your own recipes.  There are some rules to be followed, and weighing accurately is important, but the rules create a framework that you can work within to be creative. Once you understand what’s going on in a recipe, and the ratios that  make things work, you *can* play around with baking recipes. Understanding that is really liberating and opens up a whole creative world.

To do this successfully, you need to understand which elements are important to the structure of the cake, and which you can safely play around with.

This weekend, I made a cake with fruit baked into the top. This can be pudding, with custard or creme fraiche, a cake for afternoon tea (or even a late breakfast). It doesn’t require filling or icing, and can be served warm, so it’s a great last-minute option for dinner.

The recipe I started with is from Donna Hay’s book, ‘Off the Shelf’ – a book about cooking from the pantry. This one, and several earlier Donna Hay books are hard to find now in the UK, but they are really lovely. Donna is the Martha Stewart of Australia (but nicer than that sounds). She is a great food stylist and photographer as well as a cook, so all her books and her  bi-monthly magazine are beautiful, with big pictures of all the dishes.

This recipe is for a peach and raspberry tart with a sponge base. The original recipe is as follows (converting the cup measures to grams):

• 125g butter, softened
• 225g caster sugar
• 1 tsp vanilla extract
• 2 eggs
• 185g self-raising flour
• 2 peaches, halved and cut into thin wedges
• 150g raspberries
• 2 tablespoons icing sugar

[You can find the full recipe (American version) here: http://articles.nydailynews.com/2002-06-02/entertainment/18194663_1_raspberries-tart-peaches]

Just looking at the ingredients list, and the order they are presented in, I can guess  at the method and which ingredients I need to leave alone. And the method confirms this – you cream the butter and sugar together until fluffy, add the vanilla and eggs, mix the flour in gently, and then top with the fruit when the mixture is in the tin.

In a recipe like this, the ratio of the butter to sugar to flour to eggs is important. With enough knowledge, you can start playing with this too, but it’s much harder to get right.

The bits that you can safely play with are the fruit, and to a certain extent, replacing some of the flour.

For the fruit, the main thing to bear in mind is making sure that the fruit you use releases a similar amount of juice, or the finished cake could be either too dry or too soggy. Strawberries, for instance, are very juicy and get very wet when cooked. Apples and pears release much less liquid. Stone fruit such as peaches and plums, and berries, are somewhere in between.

So when I decided to replace peaches with apples, and raspberries with blueberries, I was confident that the blueberries would behave in a similar way to the raspberries. However apples give up less juice and need more cooking to become soft than peaches. I solved this problem by gently cooking the apple slices in butter before putting them on top of the cake. This made them slightly softer, giving them a head start in the cooking. They were cooked just until starting to become translucent, but still firm enough to hold together in slices.

If you did end up using much juicier fruit, you can compensate by adding something more absorbent to the flour – cornmeal, polenta, semolina will all absorb more liquid (that’s a good trick for pastry with fruit on top as well).

For this cake, I wanted to add both moisture and a different flavour by adding ground nuts to replace some of the flour. Ground nuts have a good deal of oil in them, so they don’t behave exactly like the flour. They won’t provide the structure that flour would, so the cake may sink more (although with fruit on top, this one won’t rise very high anyway). It will also keep the cake nice and moist as it keeps. I was going to use ground almonds, but then saw ground hazelnuts on special offer after passover, so used them instead.

So the final recipe I ended up with is as follows:

Apple, Blueberry and Hazelnut cake

Recipe adapted from Donna Hay’s Off the Shelf.

Oven preheated to 180C/160C fan.

• 2 apples (Braeburn), cut into thin wedges,

— Gently fried in butter until they have softened slightly and lost some of their opacity. Put aside to cool.

• 125g butter, softened
• 225g caster sugar
• 1 teaspoon vanilla extract

— all beaten together in the KitchenAid until light and fluffy

• 2 eggs

— beaten together, and then slowly beaten into the creamed mixture

• 145g plain flour (forgot about the self-raising part, and it was fine!)
• 45g ground hazelnuts

— added to mixture and mixed just to combine.

Scraped all of this into a lined and greased 9 inch/22cm springform tin.

Arrange the apples on top and sprinkle over a carton of blueberries (around 150g – 200g).

Bake for 1 hour, until the cake risen between the fruit is golden, and springs back. You can also use a skewer to test for crumbs, but pick a point in between the fruit.

Put on a rack to cool, and sprinkle with icing sugar before serving.

The final cake is firm and moist, slices cleanly and supports the fruit without it sinking through. It’s perhaps a touch on the sweet side, so I might consider experimenting with reducing the sugar in future. That is the sort of thing you want to do gradually, as you will affect the ratio of the cake.