Place the cherries, their syrup and the sugar in a saucepan. Bring to a boil, reduce the heat and simmer gently for about 20 minutes. Using a slotted spoon, transfer the cherries to a bowl. Set aside. Reduce the syrup until 125 ml (1/2 cup) remains. Add the cocoa powder and bring to a boil while whisking. Return the cherries to the saucepan. Cover and refrigerate until lukewarm or chilled.
ASSEMBLY
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