Blend ingredients: In a high-speed blender, combine tahini, milk, sweetener, vanilla ice cream, frozen banana (if using), cinnamon, and a pinch of salt.
Add ice: Add a few ice cubes for extra chill and texture, especially if not using frozen banana.
Blend until smooth: Blend for 30–60 seconds until creamy and fully combined.
Taste and adjust: Add more sweetener or tahini to taste. Blend again if needed.
Serve: Pour into chilled glasses and optionally top with a drizzle of tahini, a sprinkle of sesame seeds, or chopped pistachios. Serve immediately.