Preheat oven to 320 and line two baking sheets with parchment paper.
In a large mixing bowl combine the powdered sugar, cocoa powder, salt and chocolate chips.
Once combined, add the eggs whites and vanilla and mix until just combined through.
Spoon the batter onto the baking sheets in 12 evenly spaced mounds, 6 on each baking sheet and bake for 15 minutes, until the tops are glossy and lightly cracked;
Let cookies cool completely and then serve.