Put 8 of the eggs in a pan of cold water. Bring to the boil, cook for 5 mins, then quickly lift out of the pan and plunge in a big bowl of cold water to cool. Once cool enough to handle, peel.
While the eggs cool, put the oil, onions and garlic in a frying pan. Fry very gently until really soft and just starting to turn golden. Add the spices and fry for a few mins more. Tip into a food processor and whizz to a paste, then add the chickpeas and coriander leaves, and pulse until finely chopped but not pasty. Stir in the wholemeal breadcrumbs, flour and final egg, beaten first with a fork, with a good amount of seasoning.
Divide the mixture into 8. Take a portion at a time and flatten between your hands (rub your hands with a little more oil if it’s sticking to your fingers too much). Roll 1 of your peeled eggs in a little flour, shake to remove the excess, then wrap the falafel mixture around it, moulding it to completely cover the egg and squishing it together at the joins to seal. Repeat to cover all the eggs. Tip the panko or dried breadcrumbs onto a plate and mix in the sesame seeds. Roll each egg in it to coat. Can be made 1 day ahead, loosely covered with cling film and chilled.
Get a large, deep saucepan and half-fill it with oil, or use a deep-fat fryer. Heat until a bit of bread browns in about 30 secs. Add a couple of eggs at a time and fry, turning, until really golden and crisp, about 2 mins. Lift onto kitchen paper to drain while you cook the rest of the eggs in batches. Season with a little more salt and eat warm or cold.