In a small bowl whisk together buckwheat flour, sorghum flour, white rice flour, baking soda, salt, and cinnamon.

In the bowl of a stand mixer fitted with the paddle attachment (or in a large bowl using a hand mixer) beat butter and brown sugar together until pale and fluffy.

Add egg yolk, vanilla extract, and milk, and beat until well combined. Reduce speed to low and add whisked dry ingredients. Mix until completely combined.

Switch to a wooden spoon and mix in chocolate chips and toasted buckwheat groats. Chill dough for at least 20 minutes to obtain the perfect texture.

Preheat oven to 180°C and line two baking trays with baking paper.

Roll tablespoon-sized portions of dough into balls and place on lined baking trays. Leave space for spreading.

Bake for 12 to 15 minutes or until the edges are golden. The centres will still be soft (this makes for chewy cookies). Remove and cool completely on baking sheets. Store cookies in refrigerator for maximum chewiness for up to four days.

{ NOTES } To toast the buckwheat groats: preheat oven to 180°C. Spread buckwheat groats across a rimmed baking sheet. Cook for 10 to 15 minutes. The groats should start to smell toasty and darken in colour. Remove from oven and allow to cool completely before using in recipe. You can find uncooked buckwheat grain at some supermarkets and most health food stores.