Turn the chicken legs over so you can see the white line that marks the divide between the thigh and drumstick. Slice through the flesh. Find the joint with your fingertips. Slice through it.
Heat the oven to 200°C/Fan 180°C/Gas 6. Measure out 1 tbsp flour. Sprinkle onto a plate. Season. Crack the egg into a shallow plate. Beat it with a fork. Sprinkle the breadcrumbs on another plate.
Grease a baking tray with a drizzle of oil. Dip the chicken in the flour, then the egg, then the breadcrumbs. Pop on the tray. Bake for 35 mins till golden and cooked through. Fill the kettle and boil it.
Peel the potatoes. Chop into small chunks. Peel and slice the onion. Rinse and finely shred the kale. Fill a pan with hot water from the kettle. Add the kale. Simmer, without the lid, for 3-4 mins to just cook it. Lift out of the pan with a slotted spoon. Put to one side.
Bring the pan of water back to the boil. Add the potatoes to the boiling water. Simmer for 15-20 mins till they’re soft. Dissolve the stock cube in 200ml hot water from the kettle.
Melt half the butter with the remaining flour in a small pan. Stir constantly for 1 min. Take off the heat. Slowly whisk in the milk, then the stock. Pop back on the heat. Stir for 2 mins till thickened. Cover and set aside.
Drain the potatoes. Mash with the remaining butter. Taste and season. Pop on the lid to keep the mash warm.
Warm a drizzle of oil in a frying pan. Fry the onion for 5 mins till it’s glossy. Add the kale. Cook for 1 min. Serve the chicken with the mash, gravy and kale.