Fat Free Chocolate Cake

Pre-heat the oven to 180C (165C fan) 350F. Butter & flour (or use cocoa powder) two 20cm sponge tins or cake tins. Make the instant coffee with the cup of boiling water and leave it to one side to cool a bit.

Prepare the prune puree: put 250g of pitted prunes and 1/2 cup water into a blender or food processor and blend until smooth. Sometimes I remove a few prunes and replace them pitted dates for extra sweetness/richness.

Sift together the flour, cocoa, baking powder, baking soda and salt in a large bowl. Roughly chop the chocolate (if using any) and put it in the bowl as well. It doesn't matter too much about the size of the pieces but the larger ones create bubbles of chocolate throughout the cake.

Use a food processor with the whisk attachment to beat the eggs and egg white until creamy, then add the sugar a little at a time and keep whisking until light in both colour and texture. With the processor still going add the milk and the vanilla extract and keep whisking.

Now add the prune puree to the eggs and milk, while still whisking. Keep the food processor going now for a few minutes, because the more air you get into it at this point, the better.

Pour the egg/sugar/milk/vanilla/prune mixture into the dry ingredients and start to fold in, then add the cooled coffee and fold until it is almost incorporated and the mixture is smooth. Don't spend too long folding as the baking soda will already have started reacting with the coffee and starting the rising process.

Pour the mixture into the tins and bake until firm, 20-30 mins depending on your oven and whether you want collapsingly moist like a fondant or firm for a sandwich cake to be decorated. I've known it to take 35mins without making the cake dry.

Cool in the pans on a rack for 10 minutes, then remove the cakes from the pans and cool completely on the rack before decorating. They can be sandwiched together with a filling of your choice (raspberry jam or pureed cherries with kirsch are lovely, but children always want chocolate butter icing or Nutella). Decorate the outside if you wish, with cream or more icing.

If cooked firm, this cake is very strong and I have made 4- or 6-layer versions of it with lots of tempered chocolate poured over the top (such as Scooby Doo would like to eat), simply to see the faces of the children when I carry it into the room.