Heat cream over medium heat, whisking occasionally. The cream should not reach a simmer or boil, this risks the cream overflowing the pot or scalding. It needs to be just hot enough to melt the chocolate and dissolve the sugars. If the sides of the pot feel quite hot, and the cream releases steam when whisked, it is ready.
While the cream heats, scale the sugars and Guittard Cocoa Rouge in one bowl.
Scale the 61% Guittard Chocolate in a separate bowl and set aside.
Once the cream is hot enough, remove from heat and add all of the dries to the pot followed by the 61% chocolate.
Whisk until incorporated, paying special attention to the bottom and sides of the pot.
Using an immersion blender, blend the ganache until it appears smooth and shiny.
Transfer the ganache into a 4 quart container, allow to cool to room temperature
Pour ice cream base into the ganache and blend with an immersion blender until completely incorporated.
Freeze according to your ice cream maker's instructions.