Preserve call stack of call to Timer.schedule in java

I have a daemon thread running which calls a function (prepareOrder) whenever the cook is not busy and there are orders to be delivered. The prepareOrder calls the orderComplete function after a certain interval of time depending upon the time required to complete the order. Now the problem i am facing is only the last call to the prepareOrder gets displayed on sout.

The daemon

package ui;
import Model.takeOrderModel;
public class daemonThread extends Thread{
    //call this method in the main method of driving fucntion
    private  takeOrderModel orderModel;
    daemonThread(takeOrderModel orderModel){
        this.orderModel = orderModel;
    }
    public void assignCook(){
        while(true){
            int toComplete = orderModel.toCompleteOrders.size();
            if ( !orderModel.cookBusy && toComplete>0 ) orderModel.prepareOrder();
        }
    }
}

The prepare order function.

 public void prepareOrder(){
    // pick the last element from list
    if (toCompleteOrders.size() > 0){
        String nextPrepare = toCompleteOrders.get(toCompleteOrders.size()-1);
        order orderToComplete = allOrdersPlaced.get(nextPrepare);
        completeOrder(orderToComplete);
        toCompleteOrders.remove(nextPrepare);
        }
    }

    //Helper function to prepareOrder moves an order from toComplete to prepared order
    private void completeOrder(order orderToComplete){
        changeCookState();
        new java.util.Timer().schedule(
                new java.util.TimerTask(){
                    @Override
                    public void run() {
                        changeCookState();
                        preparedOrders.add(orderToComplete.id);
                        deliverOrder(orderToComplete.id);
                    }
                }, (long) (orderToComplete.timeToComplete*60)
        );
    }

    public void changeCookState(){
        this.cookBusy = !cookBusy;
    }

    // MODIFIES removes a order from the prepared list and puts it in delivered list
    public String deliverOrder(String completedOrder){
        preparedOrders.remove(completedOrder);
        deliveredOrders.add(completedOrder);
        System.out.println(String.format("The order of %s is here", allOrdersPlaced.get(completedOrder).customerName));
        return String.format("The order of %s is here", allOrdersPlaced.get(completedOrder).customerName);
    }

The main function driving code.

orderMachine.takeNewOrder(fullMeal, "Tom");
orderMachine.takeNewOrder(halfMeal, "Bob");
daemonThread backThread = new daemonThread(orderMachine);
backThread.setDaemon(true);
backThread.assignCook();

Now for me only the last placed order("Bob") gets printed on sout. How can all calls created by Timer.schedule stay in stack.