Brew your coffee and let it cool to room temperature.
In a blender, combine the cooled coffee, Greek yogurt, protein powder, sweetener, vanilla extract, salt, and cocoa powder (if using).
Blend until smooth and creamy, ensuring everything is well combined.
Pour the mixture into an ice cream maker and churn according to the manufacturer’s instructions.
If you don’t have an ice cream maker, pour the mixture into a mixing bowl and freeze for 30 minutes.
Stir the mixture to break up ice crystals, then return it to the freezer for another hour.
Scoop and serve your delectable coffee protein soft serve immediately for best results.