Combine cream, sugar and salt in a saucepan over low heat. When bubbles form around the edges of pan, turn off the heat. Don’t boil. Let steep for 5 min.
Stir in chocolate chips until melted and smooth. Transfer chocolate mixture to a clean container, cover and refrigerate until firm (approx. 2 hours).
Sift cocoa onto a plate. Using cool hands, gloves or a melon baller, shape chocolate mixture into small balls and roll in cocoa to coat. Transfer to a parchment paper-lined baking tray and refrigerate until firm. Store in an airtight container in the fridge for up to 2 weeks, or in the freezer for up to 2 months.