Preheat the slow cooker if necessary; see the manufacturer's instructions. Put the teabag into a jug or teapot, add the boiling water and leave to soak for 2–3 minutes. Remove the teabag and pour the tea into the slow cooker pot.
Add the whole prunes and figs, the sugar and vanilla extract to the hot tea, sprinkle with the orange rind and mix together. Cover with the lid and cook on low for 8–10 hours or overnight.
Serve hot with spoonfuls of natural yogurt and a sprinkling of muesli.