Super delicious; you might get tired of chocolate while eating it.
Put the protein powder and unsweetened cocoa powder in a bowl.
Add almond milk and banana, then blend until smooth.
Add erythritol and mix again.
Add ice and blend to your desired consistency.
Pour the mix into a container and freeze for at least 2 hours.
Before eating, take it out and leave at room temperature for 5 minutes, then scoop.