Preheat the oven to 180C/350F and grease and line an 8x8 inch square pan.
Place sugar into a large bowl and pour the melted butter over it, mix with a whisk until well combined and smooth. Add in the egg and vanilla and mix until combined.
Add in the pumpkin and mix until well combined and smooth.
In a medium sized bowl, place the flour, salt, spices and chocolate chips and stir until the chocolate chips are coated in flour.
Add the flour mix into your wet ingredients and stir until combined - don't be tempted to beat or over mix otherwise you'll end up with rubbery blondies.
Tip the mix into your lined pan and smooth until level with a spatula/wooden spoon.
Place in the oven for 25-30 minutes until an inserted skewer into the centre comes out clean. They will still look a little dark/moist in the middle, this is fine.
Leave to cool in the pan for at least and hour before transferring to a wire rack.
Once cool, slice into 9-12 pieces.
Blondies will keep in an airtight container, at room temperature, for 3 days.