Tear up the bread into rough pieces and place them in a large mixing bowl.
Add the raisins, golden raisins, ginger, cinnamon, and nutmeg, then mix well with your hands.
Pour in the milk and cream. Use your hands to squash the mixture together, until the bread is broken down and fully saturated.
Add the egg and sugar, and stir well to combine, then leave to soak for 15 minutes.
Grease and line an 8-inch square baking pan with parchment paper and preheat the oven to 350 F.
Once the bread mixture has soaked for 15 minutes, stir in the melted butter.
Transfer the mixture to your prepared baking pan and bake for 90 minutes — if it starts to become a little too brown on top, simply cover with foil.
Remove the bread pudding from the oven and leave it in the pan for about 10 minutes before transferring to a wire rack to cool. Cool completely before slicing.