Slice up the chicken breasts into even strips. Place the buttermilk and hot sauce in a small bowl and mix together. In a separate bowl, stir together the breadcrumbs, chilli flakes, salt, pepper and parmesan. Grease a baking tray with olive oil.
Coat each chicken strip in the buttermilk mix then drain and coat in the breadcrumbs. Line onto the baking tray and bake for 20-30 minutes until the crumb coating is crisp and the chicken is cooked through.
While the chicken is cooking make the gravy. Melt the butter in a saucepan then add the flour. Stir and cook out for 1 minute then add the stock cubes and stir until dissolved. Gradually whisk in the hot water until you have a thick gravy then add the sage and reduce to a thick sauce consistency.
When the chicken is ready, serve up alongside the gravy with some killer french fries.