Place the chicken in a large bowl with the olive oil, sage, garlic and lemon zest strips and juice. Mix well, cover with cling film (plastic wrap) and leave to marinate for 2 hours.
Pour the oil into a large, deep frying pan and heat it to 160°C/315°F on a cooking thermometer. (If you don’t have a thermometer simply drop a few breadcrumbs into the hot oil – if they sizzle and rise to the top within 30 seconds then the oil is ready.)
Tip the flour on to a large plate, then tip the breadcrumbs on to another and the beaten eggs into a shallow bowl. Take out the chicken from the fridge and remove the lemon zest strips. Carefully take a few of the chicken pieces and roll them in the flour. Once they are fully coated, roll them in the beaten egg and finally roll them in the breadcrumbs. Coat a few pieces at a time, so as not to overcrowd the plates.
When the chicken is nicely coated in the breadcrumbs, start frying it in the hot oil – again, do this in batches. Once each batch is dark golden all over and crisp, remove the chicken from the oil with a slotted spoon and drain it on kitchen paper. Transfer them to a metal baking tray and keep them in a warm oven (about 140°C/120°C fan/275°F/Gas 1) while you fry the remaining batches.
Serve the chicken immediately with a sprinkle of flaky sea salt, a squeeze of fresh lemon – and a cold beer.