Preheat the oven to 160 degrees C. Grease a 20x30cm baking dish.
In a large bowl, mix together the potato flour, rice flour, sugar, cocoa powder, bicarbonate of soda, cream of tartar and salt. Blend together the bananas and oil in a separate bowl. Stir the banana mixture into the dry ingredients until well blended. Spread evenly in the bottom of the prepared pan.
Bake for 20 to 25 minutes in the preheated oven, until they appear dry on the top. Cool completely and cut into squares.
Wow. The first time I made this for a gluten dairy free friend, every one loved it! It was a bit oily for my liking, and didn't keep as well as regular brownie. Today I substituted the oil for apple puree. It took an awesome brownie to new heights. Can't wait to hear what my friend says! - 26 Nov 2012
Just a query on this recipe, can someone please inform me what measurement is the cream of tarter? 1/2 a .......TSPN? 1/2 a TBSPN? 1/2 a cup?
I have just tried it with 1/2 a TSPN, & have also used 1cup of puréed apple with 1/2 cup oil. Looking forward to the end result!. - 21 Feb 2014