Put the butter, chocolate and marshmallows in a heatproof bowl, resting over a pan of simmering water. Heat for 5 minutes to soften.
Cut 6 tiny orange wedges, then finely grate the zest from the remainder.
Add the boiled water and orange zest to the chocolate mixture; heat and stir together for about 5 minutes until everything is properly melted (the marshmallows tend to take longer than the chocolate). Remove the bowl from the heat and cool for a few minutes.
Fold the cream into the chocolate mixture and stir through until the mixture is fully combined.
Creme fraiche or fromage frais also work well and can help reduce the calories!
Perfect calorific comfort food and seriously chocolatey!
Try it flavoured with fresh mint or topped with strawberries too!
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