Leave the chickpeas soaking overnight, at least 12 hours before preparing your falafels.
Once your chickpeas have been soaking for at least 12 hours, rinse them and remove the excess of water. Add them in a food processor and blend for a couple of seconds.
Add to the food processor the onion, broccoli, fresh coriander, fresh parsley, coriander powder, cumin powder, black pepper and salt.
Blend all the ingredients until you have a well-combined mixture. It shouldn't be mushy as the balls will be too dense, but it needs to be blended enough for the dough to not fall apart when frying them.
Using your hands or using a falafel press, form the dough into round shapes. Make sure the size is not too small or too big. It should be around the size of your palm.
Heat up some neutral oil in a small frying pan so you don't have to use that much oil. Fry the falafels until they are brown and crispy on the outside. If the falafels are shaped correctly, not much oil will go inside. The inside part will still be really fresh and light.
Cut the Pita Bread in half, spread some hummus and spicy sauce (optional) on the bread, add some fresh chopped tomatoes and cucumber drizzled with some olive oil, add lettuce and finally the homemade falafels. Top the sandwich with green or black olives. Optionally, can add some yoghurt sauce as well.