Add chocolate chips, coconut milk, coconut sugar, salt, and coconut oil, stir to combine. Next, cover and cook on low 2 hours without stirring. It's important that the lid remains on during the 2 hours.
After 2 hours, turn the slow cooker off, uncover, and add vanilla. IMPORTANT; Do not stir fudge mixture at this point. Allow to cool to room temperature, or it reaches 110 degrees with a candy thermometer.
Once cooled, use a large spoon, stir vigorously for 5-10 minutes until it loses some the gloss.
Lightly oil an "8x8" square pan. Pour fudge into pan, cover and refrigerate 4 hours or until firm. This fudge is very rich and meant to be eaten on occasion as a treat.
Canned coconut milk can be found in the Asian or organic sections of most grocery stores.
I used dark chocolate chips because of their health benefits. Ghirardelli is a good brand and works well with this recipe.