Combine prunes, currants, raisins, cranberries, dates, almonds, candied orange peel and orange rind in a bowl. Combine orange juice, muscat, Grand Marnier and quince paste in a small saucepan, stir over low heat until quince paste is melted (4-5 minutes), then pour over dried fruit mixture, stir to combine. Cover with plastic wrap and stand for 4 hours or overnight, stirring occasionally.
Beat butter and sugar in an electric mixer until light and fluffy, add eggs one at a time, beating well after each, then transfer mixture to a large bowl. Add breadcrumbs, flour, milk, spices, bicarbonate of soda and ½ tsp sea salt, stir to combine, then stir in dried fruit mixture. Spoon mixture into a well-buttered 2½ litre-capacity pudding basin, cover closely with a round of baking paper, then with two layers of foil, and secure with string.
Place pudding in a large saucepan, pour in enough hot water to reach just below rim, cover and simmer over low heat for 5 hours, adding more hot water as necessary. Cool in basin for 20 minutes.
Meanwhile, for muscat custard, bring cream, milk, vanilla bean and vanilla seeds to the simmer in a saucepan over medium-high heat. Whisk yolks and sugar in a heatproof bowl until thick and pale (2-3 minutes), then pour over cream mixture, whisking continuously to combine. Return to pan, stir over medium heat until mixture coats the back of a wooden spoon thickly (3-4 minutes), strain through a sieve into a bowl, stir through muscat and set aside. Serve warm or chilled. Makes about 1 litre.
To serve, unmould pudding, dust heavily with icing sugar and serve with muscat custard and raspberries. Pudding can be refrigerated for up to 1 month. To reheat, steam again in basin in a large saucepan of simmering water for 1½ hours.