In a large mixing bowl, combine the flour, ginger, cinnamon, salt, cloves, pepper, lemon zest, bicarbonate of soda and baking powder. Mix through with your hands or a whisk.
In the bowl of a stand mixer, combine the butter, sugar and molasses and whisk until combined. (I used my stand mixer for this because the molasses are so sticky and difficult to work with, you can also use a handheld mixer).
Crack in the eggs and whisk until combined.
Add the flour mixture to the wet mixture and whisk to combine.
Wrap the dough in clingfilm and pop in the fridge for an hour to set. (I divided mine into 4).
Preheat oven to gas Mark 4. Line three trays with greaseproof paper.
Lightly flour your work surface and roll out the dough until it is 1/4 inch thick.
Use gingerbread cutters to cut out shapes and place onto the pre lined tray.
Place trays in the oven. Bake for 9 to 11 minutes. I prefer them crisp so I left them for 11 minutes. You will need to check on them depending on what shelf they got in the oven!
Blend the pistachios, brown sugar and cinnamon until crumbly.
Top the gingerbread with the melted chocolate and pistachio/cinnamon mix.