Preheat the oven to 350F/177C. Butter and flour two, 8-inch cake pans and set them aside. Place the butter, sugar, eggs and vanilla into mixer bowl and whisk on medium speed for 3 to 4 minutes, or until light and fluffy. In a separate bowl, combine the flour, cocoa powder, salt and baking powder. Sift the dry ingredients into creamed mixture, alternating with milk; whisk well after each addition. Watch my video recipe to see how I do it.

Divide the chocolate cake batter evenly between the two prepared cake pans. Bake in preheated oven for 30 to 35 minutes, or until a toothpick inserted into the center comes out clean. Allow the cake layers to cool in the pan for about 20 minutes, then turn out onto a wire rack to cool completely. When cakes are completely cooled, use a long knife to level off the top of each layer.

For Frosting: place the softened butter into a mixer bowl and whisk on high speed for 7 to 9 minutes, until the butter is whipped and fluffy. Next, add in the dulce de leche, vanilla, salt and cocoa powder. Whisk again on medium-high speed for 2 to 3 minutes, then add in the confectioner's sugar. Whisk again on high speed for 2 to 3 minutes, until the frosting is light and fluffy.

For the filling, mix together caramel sauce and salted peanuts and set aside.

To assemble cake: spread a generous amount of frosting onto the first cake layer and pipe a barrier ring of frosting around the cake layer. Fill the inside first with the marshmallow cream, then fill it with the prepared caramel and peanut mixture. Watch my video recipe to see how it's done. Top with second cake layer and frost the top and sides of the cake with a crumb coat of frosting; refrigerate the cake for 15 to 20 minutes. Remove the cake from the fridge and frost with final frosting layer. Garnish the top with dollops of cream and with chopped snickers bar. If not enjoying the same day, refrigerate the cake.