How to Make It
In a medium nonreactive saucepan, combine the sugar with 1 cup of water and stir over moderately low heat until the syrup is clear, about 4 minutes. Pour into a heat-proof bowl.
In the same saucepan, cover the apricots with 2 cups of water and bring to a boil. Cover and simmer over moderate heat, stirring occasionally, until pulpy, about 25 minutes. Stir in the syrup.
Strain the apricot soup through a fine sieve into a nonmetallic bowl and refrigerate until chilled or for up to 1 day. Stir in the Champagne just before serving.