Preheat the oven to 220°C and line two large baking trays with greaseproof paper.
Sift flour and salt, stir in butter and lard, then add lemon juice and iced water to form dough.
Shape dough into a block and chill in the freezer for 10 minutes.
Roll pastry to 5mm thickness, fold into thirds, seal, turn, roll again, and freezer-chill for 5 minutes.
Repeat the rolling and folding twice more, then refrigerate for at least 20 minutes.
Roll quarters of pastry to 3mm thickness on a floured surface and place on lined trays.
Prick pastry with a fork, dust with icing sugar, and chill for 5 minutes.
Cover pastry with paper and another tray, bake for 10 minutes, remove top tray/paper, and bake 10 minutes more.
Cool pastry and cut into 10cm x 5cm rectangles.
Whisk eggs and yolks together in a large bowl.
Melt lemon juice, zest, butter, and sugar in a bowl over simmering water.
Whisk hot butter mixture into eggs then return to heat, whisking until thickened.
Cover lemon curd with clingfilm and chill.
Purée half the ginger with all the syrup and finely chop the remaining ginger.
Beat cream, crème fraîche, and cream cheese until smooth, then fold in zest, ground ginger, and ginger purée.
Fold 125ml of lemon curd into the cream mixture and spoon into a piping bag with a 1cm nozzle.
Dissolve sugar in water over heat, add fondant icing until it reaches a pouring consistency, and tint 125ml yellow.
Coat 12 pastry rectangles with white icing, pipe yellow lines, feather with a toothpick, and let set.
Assemble by layering plain pastry with chopped ginger and cream twice, then topping with an iced rectangle.