Use them to make tea. Cut up 1 or 2 large leaves for each cup needed and pour freshly boiled water over them and let stand for 10 minutes before removing the leaves.
I tried it with Volkameriana lemon leaves and it was absolutely delicious. It didn't need sugar either. I have 2 very small Hystrix lime trees which only have about 5 leaves each so I will have to wait a while before I can try that tea