Preheat oven to 180 degrees C. Grease baking trays.
In a medium bowl, cream together the butter, white sugar and brown sugar until smooth. Beat in the egg and vanilla. Combine the flour, cocoa, bicarbonate of soda and salt; gradually stir into the creamed mixture. Fold in the grated zucchini. Drop rounded spoonfuls onto the prepared baking trays.
Bake for 8 to 10 minutes in the preheated oven. Allow biscuits to cool on baking tray for 5 minutes before removing to a wire rack to cool completely.
These were terrific. A very tasty biscuit. I found them moist , with a crunch on the outside. Will definitely make again. I did cook for an extra five minutes as I cooked three trays at once. - 24 Nov 2015
This was a complete disaster for us, and I've no idea why. I followed instructions absolutely, weighing and measuring everything.
The dough before zucchini was unbelievably dry, then my zucchini may have been to wet because they were very damp and took 3 times as long as recommended to cook. The end taste was quite bland also.
Maybe with drier zucchini, and chocolate chips they would be ok. - 09 Feb 2013