Add all ingredients to a medium bowl along with 60ml (1/4 cup) water. Mix until well combined, adding more water to reach desired consistency. Serve immediately at room temperature.
Video
Notes
Use a smooth or semi-smooth peanut butter - do not use crunchy peanut butter.
Make Ahead
Store in an airtight container in the refrigerator for up to 5 days. The sauce will thicken considerably when cold; stir in a small splash of water, a teaspoon at a time, before serving to loosen it to your preferred consistency.