Steam the Broccolini for a few minutes until it is just tender. Remove from the heat and keep to one side.
Heat the 2 tbsp of olive oil in a frying pan and gently cook the onion, garlic and chili, if using, until the onion has softened but not colored. Remove from the heat and spoon into a food processor.
Chop the flowery top section off each piece of the Broccolini, cut into smaller pieces and set aside. Roughly chop the main part of the stalk and place in the food processor, along with the chickpeas, egg, parmesan, lemon zest and basil. Blitz until you have a rough paste and then transfer to a bowl. Mix in the reserved Broccolini tops and season with salt and pepper.
Using your hands, shape the mixture into patty shapes - as small or large as you like. They can be stored in the fridge at this stage ready to cook when needed (up to 1 day before).
Heat a couple of tablespoons of olive oil in a large frying pan and fry the patties for a minute or so each side until golden. You will need to do this in a few batches, depending on the size of your pan.
Remove from the pan, and serve hot, warm or room temperature.