Instructions

1. Cut the chicken breast into thick slices.
2. Thinly slice the red onion and mix with the lime juice, caster sugar and cider vinegar.
3. In a frying pan, heat 1 tsp oil on a medium-high heat. Add the bacon and cook for 2-3 minutes or until the bacon is golden and crisp. Turn the bacon and repeat on the other side before removing from the pan and draining on some kitchen paper.
4. Arrange the cheese slices, chicken, bacon and pickled onions within the two sourdough slices.
5. Spread the outside of the sandwich with mayonnaise. Heat a small knob of butter and oil in a frying pan. Once foaming, place the sandwich in the frying pan and cook until golden brown. Turn the sandwich over and repeat on the other side.
6. Once golden, finely grate parmesan over the top using a microplane and flip again to create a parmesan crust. Remove from the heat and set aside.
7. In a clean frying pan, heat the 50g salted butter with 2 tsp harissa paste. When foaming, crack the egg into the pan.
8. Baste the egg with the harissa butter for 2-3 minutes. Once cooked, place on top of the toastie.