Put the rhubarb in a casserole dish along with the rest of the ingredients and coat the rhubarb in the syrup mixture, making sure the rhubarb is spread out evenly.

Cover the dish with foil and bake in the oven for 20-25 minutes, until the rhubarb is soft to touch but still holds its shape - how long this will take depends on the thickness of the rhubarb. Remove from the oven and allow to cool a little.

Serve while still slightly warm with vanilla ice cream.