Preheat oven to 350º F.
Lightly spray two or three 9-inch round cake pans with cooking spray and lightly dust with flour, tapping with a spoon to remove excess; set aside.
In mixing bowl, add buttermilk, water, oil, sugar, eggs, baking soda and salt; stir together until it is well combined. Add in flour and cocoa powder and whisk until smooth and there are no lumps. This batter is runny don’t stress, instead lick the bowl clean.
Pour batter evenly into prepared pan(s).
Bake for 25-30 minutes (3 pans) or 30-35 minutes (2 pans), or until you can lightly touch the center and it springs back. Cool pans on a wire rack for 10-15 minutes, then remove cakes and allow to completely cool on the wire rack. Once cooled prepare filling.
In a small sauce pan add the whipping cream and bring to a boil, remove from heat and add in chocolate chips. Do not mix or stir them in, let the chocolate sit for 5 minutes. Stir until smooth. Let it cool for about 15 minutes or until it starts to thicken. Make sure it is cool, at least to room temp, before you layer the cake.
Layer the cake by placing one cake on a cake plate or stand, then spread 1/2 cup of the ganache on top of the first layer. Set in the fridge to chill for 5 minutes. Remove from the fridge, place another cake layer on top of the ganache layer. Then spread 1/2 cup of ganache of the cake. Place in fridge to chill for 5 minutes. Remove from the fridge and add the last cake layer and add the remaining ganache on top of the cake. Chill cake in fridge for 20 minutes or until ganache is set.
Slice the cake, add one piece of cake to plate, generously drizzle with caramel sauce and sprinkle with coarse sea salt, although kosher salt would work as well.