Soak the chickpeas overnight or for at least 6 hours. They will be crunchy and edible but raw.
Preheat the oven to 220 C (fan on if possible)
Drain the chickpeas and discard the water.
Place the chickpeas, peas, and tahini (or oil) in a bullet blender or food processor, and pulse into a roughly mashed batter. Do not over-blend, your batter will be too sloppy. You may need to do this in batches or to open the blender regularly to scrape out the batter around the blade.
Scrape the chickpea batter out into a large mixing bowl.
Add the rest of the ingredients to the chickpea mixture and combine well. You can now either store the batter in the fridge or freezer for later use, or you can start rolling balls and baking.
Use an ice-cream scoop to make golf-ball sized falafel balls. You can use your hands if you don't own an ice-cream scoop.
Place falafels on a prepared oven tray (use non-stick cooking spray or baking paper) and pop them in the oven for approximately 20 minutes, turning the falafels after 10 minutes.
Remove your falafels and enjoy!