Preheat the oven to 350 degrees Fahrenheit.
Pour coconut milk in a small bowl and remove 1 tablespoon. Add in the apple cider vinegar and mix. This creates a "buttermilk" for the cake.
In another bowl, combine the flour, baking soda, and salt. Finally, in a large bowl, mix together the sugar, vegetable oil, and vanilla extract. Gradually add in the "buttermilk" and flour mixture, a little of each at a time, and whisk until the batter is smooth.
Pour this into a greased 8 or 9 inch circular cake pan. Bake for 28 to 30 minutes or until golden brown.
Now comes the fun part. While the cake is still hot, drop dollops of the peanut butter on top and spread until it coats the entire cake. Put in the refrigerator for about an hour or until the peanut butter hardens.
In the meantime, melt your chocolate chips. Once the peanut butter has hardened, pour the melted chocolate on top and spread. Return to the refrigerator for another 30 or so minutes until the chocolate hardens. Remove, cut into squares, and enjoy!