1 1/2 tablespoons blood orange marmalade
3/4 ounce fresh lemon juice
1/2 ounce Simple Syrup
1/2 ounce sherry vinegar
4 ounces chilled Italian orange soda, such as San Pellegrino Aranciata
In a cocktail shaker, combine the marmalade, lemon juice, Simple Syrup and vinegar. Fill the shaker with ice and shake well. Strain into a chilled ice-filled collins glass and stir in the orange soda.