Preheat the oven to 180°C/ 350°F/Gas mark 4. Lightly grease four mini pudding basins or ramekins with the butter.
Put the dried fruit in a bowl and cover with warm water. Leave to soak for 10 minutes.
Beat the ricotta cheese with the egg yolks in a bowl. Stir in the caster sugar, cinnamon and orange zest, and mix to combine.
Drain the dried fruit in a sieve set over a bowl. Mix the drained fruit with the ricotta cheese mixture. Spoon the mixture into the basins or ramekins.
Bake in the oven for 15 minutes. Leave to cool, then refrigerate overnight before serving.