Blanch the cavolo nero leaves in a pan of boiling water for 1 minute, then drain well squeezing the leaves to remove the excess liquid. Pat dry with paper towel.

Place the ricotta, kale, parmesan and lemon zest into a food processor and pulse for 30 seconds or until well combined.

Transfer the mixture to a large bowl, stir in the egg, the breadcrumbs and mix thoroughly to combine. Season with the salt and pepper. Add more breadcrumbs if the mixture is still too soft/liquid.

Form into 12 patties.

Heat the olive oil in a clean frying pan over medium heat. Fry the patties in two or three batches for 2-3 minutes per side.