Step 3: Heat half of the olive oil in a large saucepan. Add the onion and sautÃ© for three minutes.
Step 5: Add the chickpeas and cook for another minute.
Step 7: Place half of the chickpeas and the onion in a food processor. PurÃ©e until you have a smooth mixture.
Step 9: Tip into a bowl and add the remaining chickpeas, coriander, egg and mashed potato.
Step 11: Mix well, then shape the mixture into four burgers and sprinkle with the sesame seeds to coat.
Step 13: Place the remaining olive oil in a frying pan and gently cook the burgers on a very low heat, for about five minutes on each side.
Step 15: Toast each half of the burger buns, then place a burger in each, topping with a tomato slice, red onion ring and a lettuce leaf.