Soak: Place chickpeas in a large bowl, cover with plenty of cold water and soak for 24 hours or overnight. Drain well.
Chop: Finely chop the onions & garlic on a grater and add it to the blending pot.
Mix: Add chickpeas, roughly chopped herbs, baking soda, cumin, coriander, chilli flakes, salt, and pepper.
Blend: Process for 30 seconds. Scrape the mixture down the bowl's walls and process again for about 10 seconds. Scrape again, repeat a couple more times until you have the right consistency: the mixture should look like coarse. Don’t overprocess; you should not have a paste.
Refrigerate: Transfer the mixture to a bowl, cover and refrigerate for at least 4 hours and up to 24.
Make balls: Add sesame seeds just before forming and cooking the balls. Scoop with a falafel scoop or your hands and form balls or discs. I usually make about 10 balls of approximately.