100g butter, melted, plus a little extra for the dish
250g self-raising flour
140g caster sugar
1 tsp baking powder
zest and juice 1 orange
100g orange milk chocolate or milk chocolate, broken into chunks
single cream or ice cream, to serve
For the sauce
200g light muscovado sugar
Butter a 2-litre baking dish and heat oven to 180C/160C fan/gas 4. Put the kettle on. Put the flour, caster sugar, 50g cocoa, baking powder, orange zest and a pinch of salt in a large mixing bowl. Whisk together the orange juice and any pulp left in the juicer, the eggs, melted butter and milk, then pour onto the dry ingredients and mix together until smooth. Stir in the chocolate chunks and scrape everything into the baking dish.
Mix 300ml boiling water from the kettle with the sugar and cocoa for the sauce, then pour this all over the pudding batter – don’t worry, it will look very strange at this stage! Bake on the middle shelf of the oven for 30 mins until the surface looks firm, risen and crisp. As you scoop spoonfuls into serving bowls, you should find a glossy, rich chocolate sauce underneath the sponge. Eat immediately with vanilla ice cream or single cream.