For the dough, put the flour into the bowl of a freestanding mixer fitted with a dough hook. Add the salt and sugar to one side of the bowl and the yeast to the other. Add the butter, milk and 150ml/5fl oz water. Mix until a dough forms then knead in the mixer for 5 minutes. Cover the bowl with cling film and leave to prove in a warm place for 1 hour, or until doubled in size.
Once the dough has proved, divide it into 2 equal parts. Flatten each piece of dough out and add the cardamom to one and the nutmeg to the other. Knead to distribute the spices and knock out the air.
Divide each piece of dough into 8 equal parts. Roll the cardamom dough into balls and the nutmeg dough into fingers. Place on baking trays, cover and leave to prove for 30 minutes.
Preheat the oven to 200C/180C Fan/Gas 5. Bake the bread for 10 minutes.
For the almond custard, warm the milk and sugar in a saucepan. In a bowl, whisk together the egg yolks and cornflour. Slowly add the hot milk to the egg mixture stirring all the time. Return to the pan and heat, stirring all the time, until thickened. Remove from the heat and add the salt and almond extract. Cover the surface with cling film and leave to cool completely.
Whip the cream until soft peaks form, then fold into the cooled custard.
For the sour cherry jam, drain the cherries and blend them to a paste in a blender. Transfer to a saucepan and add the sugar and lemon juice. Boil the mixture until it reaches 105C on a sugar thermometer. Remove from the heat and stir in the cherry flavourings. Pass through a sieve and leave to cool completely. When cool transfer to a piping bag fitted with a small plain nozzle.
For the royal icing, beat the egg white and lemon juice using a wooden spoon until frothy, then add 3 tbsp icing sugar and beat again. Keep beating and adding a few tablespoons of icing sugar until all the icing sugar is incorporated and you have a smooth paste (if the icing is too thick add a little water to slacken). Transfer to a piping bag fitted with a plain nozzle.
For the Chantilly cream, add the cream and icing sugar to a large bowl. Whip until soft peaks form when the whisk is removed. Transfer to a piping bag fitted with a large star nozzle and leave in the fridge.
To assemble the cardamom and almond buns, cut the buns in half horizontally and fill them with the almond custard. Pipe icing on top of the bun, top with toasted almonds, a sprinkling of cardamom powder and a dusting of icing sugar.
To assemble the nutmeg and sour cherry fingers, make a deep slit lengthways in the top of the bread fingers. Pipe icing on both sides of the slits and leave to set.
Pipe some cherry jam in the bottom of the slit. Pipe the cream neatly on top and pipe two stripes of cherry jam at either side of the cream.