
In 1929, McVitie and Price introduced the Jaffa cake. While it is technically a cake (the base is Genoise sponge) it is eaten like a biscuit.

I use 2 12-hole cupcake trays - one for the jelly, the other for the cake bases.
Sift the sugar into a bowl and whisk it together with the eggs for 5-8 minutes. You want the mixture to turn pale and thicken up a bit. Technically, you need it to reach the 'ribbon' stage, which means that when you take some of the mixture out of the bowl and let it run back in, it leaves a ribbon-like trail and is not re-absorbed immediately. Fold in the flour, being careful not to knock the air out of the egg/sugar mixture. Melt the butter and add it with the almond extract. Spoon the mixture into the tin, leaving some space at the top of each cake. Bake for 8 minutes. Remove from oven and cool on a wire rack.
Place a disc of jelly on each cake base and spoon chocolate over it, making sure it goes right to the edge of each cake. Refrigerate until set, then use the back of a fork dipped in very hot water to melt 3/4 lines into the top of each Jaffa cake.
1 pack orange jelly
1 medium orange
half a cup boiling water
40 grams plain (all-purpose) white flour
40 grams caster sugar
15 grams butter
2 eggs
a few drops almond extract
100 grams dark chocolate