Preheat the oven to 325 degrees.

Line an 8×8 cake pan or baking dish with parchment. Set aside.

Combine the chocolate, butter, half and half, and granulated sugar in a double boiler.

Heat over simmering water until everything is melted and combined. Gently stir occasionally.

Remove from the heat and allow the mixture to cool to room temperature for 15-20 minutes.

Whisk in the eggs and vanilla once cooled.

Combine the flour, baking soda, and salt in a small bowl. Stir and then fold a half cup at a time into the wet mixture.

Transfer to the prepared baking pan. Bake for 50-65 minutes or until a toothpick inserted into the center comes out clean.

Cool to room temperature on a wire rack before using the parchment to lift it out of the pan and decorate.