Add the egg yolk and sugar to a small mason jar and use your small electric whisk to whip (see notes above about egg yolks)
Whip until your mixture is light, fluffy, and lighter in color
Sift the cacao powder into the egg mixture and stir to combine
Meanwhile, heat the heavy cream on the stove until steaming, but does not produce bubbles
Pour the warm cream over the chocolate chips in a heat safe bowl
Wait a few minutes, then stir this mixture together until smooth
Add everything to the pint container, including salt and gently stir until well incorporated
Freeze for at least 12 hours
Remove from the freezer and let sit on the counter for 7-10 minutes
Follow the Ninja Creami instructions to blend the mixture using the “ice cream” setting
Once the cycle is finished, remove the container and add a splash of cream in the center
Run the Creami one more time on the “respin” setting
Now the ice cream is ready to eat, or add mix ins (see my suggestions above)
For mix-ins, make a small well in the center of the ice cream container, add mix ins
Run the ice cream on the mix in setting
Enjoy right away or freeze for later!