Place the avocado in a food processor or high-speed blender and puree. Alternatively, the avocado can be mashed by hand but try to get it as smooth as possible. Place it in a small bowl and set aside.
In a medium mixing bowl, combine the chocolate chips and vanilla. Set aside.
In a small saucepan, whisk together the coconut sugar and plant-based milk. Add vegan butter and place over medium heat. Whisk continuously until at a rapid boil. Continue whisking over a rapid boil for 3 minutes. Add the avocado to the mixture, whisking in 1 tablespoon at a time until each is almost fully incorporated. Once the mixture is smooth, remove from the heat.
Pour the hot avocado mixture over the chocolate chips and vanilla and mix well with a spoon until completely combined and smooth. This may take a few minutes.
Add fun toppings like dried fruit and nuts in step 5 after spreading the fudge into the pan. My favorite additions include additional chocolate chips and walnuts.