2) Slice the bread in 1cm thick slices and remove the crusts. In the bottom of a 19 by 8cm round high souffle or baking dish, ladle about 115ml of the cooked berry mixture. Arrange slices of bread in a pattern (this will become the top when it's unmoulded) and then add more berry mixture to saturate. Continue adding bread, cutting it to fit the mould, and berries. Finish with bread and cooked berries, using all of the fruit and syrup.
3) Place a sheet of cling film loosely over the pudding. Find a plate approximately the same diameter as the inside of the mould and place it on top. Weight the mould with a heavy can and refrigerate. Remove the weight after 6 to 8 hours. Cover the pudding with cling film and refrigerate overnight.
4) Just before serving, run a knife around the outside of the pudding and unmould it upside down onto a serving plate. Serve chilled in wedges with a dollop of the rum whipped cream.
For the rum whipped cream:
1) Whip the cream in the bowl of an electric mixer fitted with the whisk attachment. When it starts to thicken, add the sugar, vanilla, and rum. Continue to whip until it forms stiff peaks. Serve cold.