Follow these simple steps to create the decadent Nutella Cake:

1. Preheat the Oven: Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
2. Mix Dry Ingredients: In a large bowl, sift together the flour, sugar, cocoa powder, baking powder, baking soda, and salt.
3. Combine Wet Ingredients: In another bowl, whisk the eggs, milk, vegetable oil, and vanilla extract until thoroughly combined.
4. Combine Mixtures: Slowly add the wet ingredients to the dry ingredients. Mix until just blended.
5. Add Boiling Water: Stir in the boiling water until the batter is smooth. This will thin out the batter.
6. Transfer Batter: Pour the batter equally into the prepared cake pans.
7. Bake: Place the pans in the preheated oven and bake for 30-35 minutes, or until a toothpick inserted in the center comes out clean.
8. Cool the Cakes: Once baked, remove from the oven and let them cool in the pans for 15 minutes. Then, transfer to wire racks to cool completely.
9. Prepare the Frosting: In a mixing bowl, whip the heavy cream until soft peaks form. Gently fold in the Nutella until smooth.
10. Assemble the Cake: Place one cake layer on a serving plate. Spread a generous layer of Nutella frosting on top, then add the second layer. Frost the top and sides of the entire cake.
11. Decorate: Optionally, drizzle more Nutella on top and garnish with crushed hazelnuts for added texture.

By following these detailed steps, you’ll create a Nutella Cake that is not only stunning but also deliciously memorable!