Making chocolate rock cakes like a 1930s housewife

The simplicity of the recipes in Lydia Chatterton's Modern Cookery (Illustrated) is encouraging me to get my baking trays out and have a go at some of the cake recipes in my grandmother's cookbooks.

Although second hand book websites give the date of this book as anything from 1917 to 1951, my guess is that this is one of a number of cookbooks that my grandmother bought as a housewife in the 1930s. The pictures also suggest that this copy, at least, dates from that period.

I've made rock cakes before but never chocolate ones. I whipped these up in less than 20 minutes including cooking time. The result was a slightly biscuity cake that the kids devoured in seconds.

Next time I cook them though, I'm tempted to take a 21st century liberty with the recipe and add some chocolate bits to the mixture for a little extra taste.