2Cupgluten free 1-1 flour mix that contains xanthan gum 338g if your mix does not contain xanthan gum add 1/2 tsp now (1g)
1Cuparrowroot starch or cornstarch 146gcornflour in the UK
1tspbaking soda 6g
⅓tspsalt 3g
1 ½Cupschopped walnuts 180gplus a few extra for the tops of the cookies
Instructions
First, make your browned butter! In a medium to large saucepan over medium-low heat, melt the 1 1/4 cup of salted butter and stir constantly until melted and simmering. Continue to simmer, on medium heat, for at least a few minutes, until the popping and hissing sounds have completely subsided (this is the water in the butter burning off – you’ll know once it’s silent). Continue to cook, stirring constantly, until the butter reaches a deep amber color and smells nutty or caramelly. The butter will foam up, so keep stirring/lifting up spoonfuls of the butter to see the color. The browned milk solids will foam up in the center of the pan – once it does that- immediately take off the burner and let sit for a few minutes, then pour (scrape ALL of the brown bits – that’s the flavor!) into a heat-proof small bowl and let it cool to room temp (it should be solid) – you can speed up the cooling process by popping the butter into the fridge fr 15 minutes.
In a large bowl, using an electric mixer, cream together the room temp browned butter, brown sugar, and white sugar until lighter and fluffy (3-5 minutes – don't skimp on this step!). Add in the egg and vanilla and banana extracts (this is the key ingredient!) and beat until smooth. Then, in a small bowl, mash the banana and then add the mashed banana to your cookie dough and beat until smooth, another 30 seconds. Add in the flour, starch, baking soda, and salt and mix by hand with a wooden spoon or spatula until fully combined (it will be quite stiff). Finally, mix in the chopped walnuts until they're fully distributed. Scoop dough into a smaller bowl, cover with plastic wrap, and chill in the fridge for two hours (if you chill it longer, you may need to bring it closer to room temp by leaving it out on the counter for an hour).
Once the cookie dough is chilled, preheat the oven to 350° Fahrenheit (180° C, no fan) and line a cookie sheet with parchment paper. Lightly grease the parchment and then start scooping out the cookie dough and rolling it into 2 1/2 inch round balls. Then press the cookie dough ball slightly so that you get a 2.5-3 inch patty (about an inch thick) then place 4-5 patties on the cookie sheet (~4 inches apart) and top with a few pieces of walnuts and bake for 9-10 minutes. Let cookies cool COMPLETELY before removing from the cookie sheet (15 minutes at least) then enjoy!