1 medium onion, peeled and sliced thinly
small bunch flatleaf parsley
陆 red pepper, de-seeded and sliced
陆 green pepper, de-seeded and sliced
200ml/7fl oz beef stock
sea salt and black pepper
olive oil
3 tbsp paprika
2 tbsp tomato pur茅e
25g/1oz butter
100ml/3陆fl oz soured cream
500g/1lb sirloin steak, trimmed and cut in strips