Preheat oven to 350. Grease two 9 inch round cake pans with shortening then cut parchment paper to fit the bottom of the pans and grease them as well. (the parchment paper is a must or the cake WILL stick to the bottom of the pans)
Sift the dry ingredients together and place in a large mixing bowl.
Add eggs, oil, milk, vanilla and beat for 2 minutes, until combined.
Scrape down sides of bowl and add hot water. Mix once more until water is combined. (Batter will be runny)
Pour into prepared pans and bake 28-30 minutes.
Cool for about 5 minutes in the pan, run a knife along the edges to loosen then transfer cakes to wire rack to cool completely.
While cake is baking, prepare frosting. Beat butter in mixer until smooth.
Add vanilla and mix until combined.
Add powdered sugar in 1 cup increments, scraping down sides of bowl after each addition. Make sure each addition is well incorporated before adding the next.
Add milk 1 tablespoon at a time until you reach desired consistency. Place frosting in fridge to cool until ready to use.
Place chocolate in a heat resistant mixing bowl, set aside.
Add cream and butter to saucepan and heat over medium heat until butter melts and cream is just coming to a boil. Remove from heat and pour over the chocolate chips. Let sit for about 1 minutes before stirring.
Beat with a whisk until chocolate is completely melted and mixture becomes smooth. Gnache will thicken as it cools. (Tip: Whisk occasionally to keep it smooth) Make sure gnache is completely cooled before pouring over frosting.
After cakes are cool, set one cake on a plate with the flat side facing up. Evenly spread one-third of the frosting over the cake to the edge. Top with the second cake layer, rounded side up. Spread the remaining frosting over the top and side of the cake. Pour the gnache over the top of the cake, starting from the center. It will run down the sides on its own.