First, preheat the oven to 350 degrees F (175 degrees C).
Using a 9 X 13-inch pan, grease and then dust it with cocoa powder. Next in a bowl, sift together the cocoa, flour, baking soda and salt. Set aside.
In a large bowl, cream together the cannabutter and white sugar until it's light and fluffy. Beat in the eggs one at a time.
Alternately, beat in the flour mixture and then the buttermilk, mixing just until incorporated. Add the boiling water and beat for approximately one full minute.
Bake in the preheated oven for 30 to 40 minutes. A trick to tell when its ready is to insert a toothpick into the center of the cake, it's ready when the toothpick comes out clean. Allow the cake to cool.
Add any frosting you wish and now you're done!