Oven 180c
Beat together the butter and sugar. Stir in the pumpkin puree, salt, spices and custard powder/cornflour.
Stir the baking powder into the mixture, then mix in the flour. The dough will be soft but will stay on a spoon unless scraped off.
Add the pumpkin seeds and 50g of the chopped chocolate. Scoop out the dough with a small ice cream scoop or dessertspoon and place on a greased baking tray. It should make 12 - 15 cookies depending on the size of your dough scoops.
Press down slightly with a spatula then place chunks of the remaining chocolate on each cookie.
Bake for 20 - 30 mins until lightly golden around the edges. If you prefer a softer biscuit, bake for 20 mins, if you prefer a crisper biscuit, bake for 25 - 30 mins.