Bake the cake:

1. Preheat oven to 350F. Prepare three 5 inch round cake pans.
2. Combine the eggs, 1/4 of the yoghurt and vanilla.
3. Place the dry ingredients in the bowl of your stand mixer and mix on low speed until combined. Add the butter and remaining buttermilk and continue to mix until everything is moistened. Increase to medium speed and beat for 1 1/2 minutes. Scrape down the sides of the bowl and gradually add the egg mixture in three batches, beating for 20 minutes after each addition. Scrape down the sides of the bowl once more.
4. Divide cake batter evenly amongst cake pans and bake for around 30 minutes or until an inserted skewer comes out clean. Cool cakes completely.

Make the filling:

1. Mix the chocolate cake crumbs and enough condensed milk to form a paste.
2. Add a splash of milk to loosen if too stiff.

Make the frosting:

1. Beat the butter until smooth.
2. Add the icing sugar and salt and beat until light and fluffy.

Assemble the cake:

1. Trim the tops of the cakes if necessary to make them flat. Take the first layer of cake, spread half the filling on top, place the second layer on top of the filling, spread the remaining filling on top and finish with the last layer of cake.
2. Frost the outsides of the cake with the frosting. It will just be a thin layer but that’s sufficient for getting the Pocky to stick to the sides. Arrange the Pocky sticks around the sides of the cake.
3. Refrigerate cake until frosting has firmed up before serving.

Source: Crumbs and Cookies