1.
Cut the grapefruit in half crosswise. Sprinkle each half with sugar or a sweetener of your choice – e.g., maple or date syrup.
2.
Place the grapefruit halves on a baking tray and bake at 200° for about 15–20 minutes, until they start to bubble and the rind is slightly roasted.
3.
Sprinkle with a little cinnamon and serve while still warm.