For the falafel batter
Preheat a waffle maker.
Add all the falafel ingredients to a food processor and blend for a few seconds. Then pulse a few times. Blend until you have a firm batter that is slightly grainy.
Place 4 tbsp of the chickpea brine in a separate bowl. Whip the brine with an electric beater until it forms stiff peaks (like a meringue). Carefully fold this into the waffle batter.
Spray the waffle maker with baking spray.
Once the waffle maker has heated up (the light will go off), place the batter in the waffle maker and cook for 8 minutes until golden and crunchy. Repeat the process for the rest.
Serve warm with the tzatziki, red onion, cucumber and mint.