Place the bread, spring onions and chives in a food processor and process until finely chopped.
Add the chickpeas and butter beans and pulse until coarsely chopped. Tip into a bowl and stir in the mustard, lemon zest, Cheddar and beaten egg.
Stir the mixture together and shape into 6 medium-sized burgers. Place on a tray and cover with clingfilm. Chill in the fridge for 30 minutes.
Heat the oil in a frying pan and cook the burgers for 3 minutes each side until golden.
Cook's tips: to freeze the uncooked burgers, simply wrap in clingfilm, then foil, and freeze for up to 3 months. Defrost completely (overnight in the fridge is best) before cooking. For toddlers: serve in mini pittas with lettuce, tomato and cucumber. For babies: try mashing the cooked beanburger or, if that’s too coarse, purée it instead.