IBA official recipe includes:
Components
90 ml – Prosecco
60 ml – Select Aperitif or the modern spritz recipe can be made using Aperol/Campari/Cynar
Soda Water – Splash
Preparation
Build all ingredients into a wine glass filled with ice. Stir gently. Garnish with slice of Orange.
Enjoy ! ADB
The Venetian Spritz features Select Aperitivo and is an “older and more mature cousin” to the Aperol Spritz