Soupe de Peches (Peach Soup)

Simmer the water and sugar together, stirring until the sugar is dissolved. Remove from heat, add the tea bag and the zest and steep for 5 minutes. Discard the tea bag. Chill until cold. Just before serving, peel and cut the peaches into 1/4-inch dice. Stir into the chilled syrup. To serve, divide the soup among 4 shallow bowls and top each with a scoop of peach ice cream.