Heat oven to 180°C or 350°F
Line a 23cm x 33cm (9 x 13 inch) pan with baking paper and set aside
Sift together the flour, spice, bicarb soda and salt into a bowl and set aside
Using a paddle attachment on your a stand mixer, beat the butter and sugars on medium until light and fluffy
Mix in the pumpkin, then the egg and vanilla
Stop the mixer, add the dry ingredients, then mix on low until almost combined
Fold through most of the chocolate chips, reserving some to decorate the top of the blondie
Spread mixture into your prepared tin, sprinkle with remaining choc chips and bake for 35-40 minutes
Remove from oven and cool completely in the pan, before cutting into desired size squares (5½ cm/2.2 inch squares will give you 24 generous blondies)