Remove the seeds of the plums and wash and slice them. Place them in a pan with the vanilla pod, apple juice and balsamic vinegar. Bring to the boil then reduce the heat to simmer for 20 minutes or until the sauce is thick and the plums are soft.
Have the kangaroo at room temperature and drizzle the olive oil over it. Heat a grill pan to hot and sear the kangaroo for approx 4 minutes each side.
Remove it from the pan and place it onto a plate. Cover the plate with foil and set aside for approx 10 minutes.
Combine the watercress and mint onto a plate and drizzle with a little lemon infused olive oil.
Serve with the kangaroo and plum sauce.