Line a 20cm square baking tin with baking paper and place the puffed quinoa and rice into a large mixing bowl.
In the bowl of a food processor blend the dates and nut butter together until smooth. Add the rest of the ingredients.
Add the date mixture to the quinoa and rice and mix until combined, then press into the lined baking tin. Use damp hands to really press it in and try to make it as even as possible.
Place the tin in the freezer for 30 minutes, or refrigerate for a few hours, before cutting into 16 squares. Keep refrigerated in a sealed container.
Rinse 170g of uncooked quinoa thoroughly. Spread it out on a baking sheet. Preheat the oven to 200°C, gas mark 6, and dry the quinoa in the oven for about 20 minutes. Place a heavy-bottomed cast iron pot over a high heat. Add the quinoa and move the pan every now and then as it starts to pop. Allow to pop until the popping becomes slower. Remove from the heat and decant into a bowl.