In a medium stockpot, combine the tea bags, sugar, and vanilla with 4 cups of water. Bring to a boil, reduce the heat to a simmer, and stir until the sugar is dissolved.
Add the nectarines and cook for 2 minutes, or until the skins are slightly loosened. Using a slotted spoon, remove the nectarines to a bowl.
Using a vegetable peeler or sharp paring knife, peel each nectarine, allowing the juices to collect in the bowl. Return the nectarines and collected juices to the poaching liquid and cook for 10 minutes more.
Transfer the fruit to a plate. Using a slotted spoon, remove the tea bags and vanilla bean and discard. Raise the heat to high and cook the poaching liquid until it is reduced to a thick syrup, about 15 minutes.
Place the nectarines in individual serving dishes and drizzle the glace over each.