Place the chickpeas in a large bowl and cover with water. Let soak at room temperature overnight.
Drain and rinse the chickpeas and set aside.
Place the sorrel in a large food processor and blitz until it resembles mulch. Place the sorrel in the center of a piece of cheesecloth and squeeze the excess moisture from the greens. Discard the liquid and set the sorrel aside.
Place the garlic, onion and cilantro in a large food processor and blitz until finely chopped. With the food processor running, start adding the chickpeas in batches.
Once the mixture is relatively uniform, add the sorrel, sesame oil, tahini and seasonings to the food processor and blitz. Stream in the lime juice while the food processor is running. Continue to blitz until the mixture resembles damp sand. Transfer the mixture to a bowl.
Take a heaping tablespoon of the mixture and form it into a ball. Repeat with the remaining mixture. Transfer the falafel to the fridge and let chill for 15-30 minutes.
Heat 2-inches of the oil of your choice in a cast iron skillet until it reaches 375°F. Try maintain this heat throughout the frying process. Add 7-8 falafel balls to the oil and fry until deep golden on one side, about 4 minutes. Roll the balls over and fry for another 4 minutes.
Transfer the falafel to a plate lined with paper towel to drain. Keep warm until ready to use.