Heat the oil in a large frying pan over high heat. Cut steak into 3cm cubes. Cook the steaks, in 2 batches, for 3 minutes each side or until browned. Transfer to the slow cooker.
Add the coconut oil to the pan. Cook until foaming. Add the onions. Reduce heat to medium-low and cook, stirring often, for 10 minutes or until browned and tender. Add the garlic and cook, stirring, for 1 minute or until aromatic.
Add the stock, Worcestershire sauce, thyme and bay leaves. Bring to a simmer. Pour over the steaks in the slow cooker. Cover and cook on High for 5 hours or until beef is tender.
Combine the cornflour with water. Add to the slow cooker. Cook for 20 minutes or until the liquid has thickened slightly. Season. Stir through the parsley.
Sprinkle with extra parsley. Serve with green beans.