Peel the quinces. Cut each one into quarters – they’re quite hard so you’ll need a sharp knife. Cut out the cores, taking care not to remove much of the quince flesh. Cut the quarters into slices. Pop in a large pan.
Crush 6 cardamom pods with the back of a knife to break them open. This will allow maximum flavour to be released during cooking. Add to the pan, scraping in any escaped seeds.
Drop in 1 cinnamon stick. Add the honey and vinegar. Pour in 300ml cold water and cover. Put the pan over a medium-low heat. Cook gently for 20 mins, stirring occasionally.
While the quinces cook, tip the pearl barley into a small pan. Pour in enough boiling water to cover the barley well. Cover, bring to the boil and then simmer for 20 mins till the barley is tender. Drain well.
While the barley cooks, peel and finely slice the red onion. Pick out any thick stalks from the watercress.
Rub each venison steak with 1 tsp oil and season well. Heat a frying or griddle pan over a medium heat. Carefully place the venison steaks in the pan. Fry for 2 mins on each side for rare, 3-4 mins on each side for medium and 5-6 mins on each side for well done. If your steaks are thick they might need a few more mins and if they’re very thin they’ll need less time.
Put the steaks on a plate, cover with foil and set aside to rest. Add another 2 tsp oil to the pan. Add the onions and cook for 5 mins till softened.
Arrange the watercress on two plates. Spoon over the barley and onions. Slice the venison and place on the salad. Dot over the spiced quinces, discarding the spices, and drizzle over the poaching liquid to serve.