Preheat the oven to 180°C/160°C Fan/Gas Mark 4.
Put the Weetabix and sultanas in a bowl. Pour the milk and water over the top and leave to soak up all the liquid.
Stir in the flour, mixed spice, sweetener and beaten egg.
Spoon the mixture into a 450g lined loaf tin and bake in the preheated oven for 1¼ hours, until cooked.
Cool on a wire rack before serving, then cut into 12 slices.by: witwitwoo