Fill a pitcher with 8 cups of water and slice the orange into pieces roughly a 1/4-inch thick. Cut them in half, or in quarters, depending on how large the mouth of your pitcher is. (You want them to be easily removed later for cleaning!)
Add the vanilla and orange slices to the water, stir well, and let the flavors meld together for 2 to 4 hours in the fridge before serving. Serve chilled, and store any leftovers in the fridge for up to 3 days.
Notes
Nutrition information is for 1 of 8 cups. This is automatically calculated, and is just an estimate, not a guarantee.