Cordials

• 1 tablespoon grated lemon rind
• 2 teaspoons grated lime rind
• 3/4 cup lemon juice
• 3/4 cup lime juice
• 1 teaspoon citric acid
• 1 teaspoon tartaric acid
• 1 1/2 cups caster sugar
• 3 cups boiling water

Place lemon rind, lime rind, lemon juice, lime juice, citric acid, tartaric acid and sugar in a heatproof bowl. Add boiling water. Stir until sugar has dissolved. Strain into a heatproof jug. Pour into hot, sterilized bottles and seal. Refrigerate until chilled. To serve: Use 1/3 cup cordial to 2/3 cup chilled sparkling mineral water or iced water. Serve with thinly sliced lemon and lime.