Preheat the oven to 190 degrees C. Grease a biscuit tray or line with baking paper.
In a large bowl, cream together the butter and caster sugar until smooth. Beat in the eggs one at a time. Stir in the vanilla and pumpkin puree until well blended. Combine the flour, bicarb, baking powder, salt, cinnamon and nutmeg; stir into the pumpkin mixture. Mix in the chocolate chips. Stir in the walnuts if desired. Drop by teaspoonfuls onto the prepared tray.
Bake for 12 to 15 minutes in the preheated oven, until edges begin to brown. Allow to cool for a few minutes on the tray before removing to wire racks to cool completely
Pumpkin puree for biscuits and pies
The pumpkin puree needs to be as dry as possible, so baking is the best method for cooking the pumpkin. One way is to cut and peel the pumpkin, dry bake it in a foil lined tray and then puree it in a food processor. Or you can leave the skin on, cut the pumpkin into larger pieces, scoop out the seeds and bake wrapped in foil. Scoop the flesh out from the skin when cooked, then puree. If you boil the pumpkin make sure it is well drained, both after cooking and after pureeing. Sweet pumpkin – such as butternut – is best for this type of recipe.
Altered ingredient amounts.
I'm American and had to convert ozs to cups. Here were my conversions: Butter - 9 Tbsp., Sugar - 3/4 cup., Eggs - 2, Pumpkin (I used canned) 1 cup., Flour - 2 cups plus 2 Tbsp., Chocolate chips - 1 cup. And the oven temp is 375 F. - 10 Oct 2010