Preheat the oven to gas 4 / 180C / 350°F and grease a 12 hole muffin tray
Mix the flour, xanthan gum, baking soda, salt and sugar in a bowl
Add the milk, oil and vanilla. Stir until just combined
Spoon an even amount of batter into each hole in the muffin tin and bake for 10-12 minutes. Cool in tins for 2 minutes then remove the cakes to a wire rack to cool completely
Melt the chocolate and dairy-free spread over a bain marie (in a bowl over a pan of simmering water). Add the orange zest and stir to combine.
When the cake bases have cooled put a tsp of marmalade in the centre of each
Spoon the chocolate over each cake and let it drip off through the wire rack so the bases don't get covered in chocolate too. It's easiest to clean up if you put a sheet of parchment paper under the rack
Put the rack in the fridge for 20 minutes to set and keep in a cool place until you're ready to eat them
Real Jaffa Cakes use a cut out circle of orange flavoured jelly/jello but for the sake of quickness I use marmalade
