For the cake:
For the cream:
For the ganache:
1. Make vanilla cake: preheat oven to 325F (160C). prepare two 9-inch (22-23cm) cake pans with parchment paper circles in the bottom and grease the sides.
2. In a medium size bowl combine flour, baking powder and salt. Stir and set aside.
3. Heat milk and butter in small saucepan over low heat until butter is melted. Do not boil. In a large bowl whisk eggs and sugar on high speed for 5 minutes, until light and pale. Add hot milk mixture, vanilla and whisk. Gradually add flour mixture and mix until combined.
4. Divide the batter equally between the prepared pans, and bake for 25 minutes, or until a toothpick inserted in the thickest part of the cake comes out clean.
5. Remove the cakes from the oven and let cool for about 10 minutes, release from the pans and place on a cooling rack to cool completely.
6. Make the pastry cream: in a saucepan, heat milk until simmering. Meanwhile, in a large bowl, whisk yolks, sugar, until smooth. Add cornstarch whisk until incorporated. Remove the milk from heat, whisking constantly, slowly pour hot milk to yolk mixture to temper. Return tempered yolk mixture to the saucepan.
7. Place the saucepan over medium heat, cook the cream, whisking constantly, until thickened, about 5-7 minutes. Remove from heat, whisk in butter and vanilla until butter is melted and incorporated.
8. Strain through a fine-mesh strainer. cover with plastic wrap, pressing it directly onto the surface of the pastry cream to prevent forming a skin on the surface. Refrigerate for at least 2 hours.
9. To Assemble: place one cake round on large plate, spoon pastry cream on the center of cake. Using offset spatula, spread evenly. Place second layer on pastry cream, bottom side up. Press lightly on top of cake to level. Refrigerate while making the ganache.
10. Chocolate ganache: Heat the cream in a small pot over medium low heat, until simmering. pour the hot cream over the chopped chocolate, let sit 2 minutes, then whisk until smooth.
11. Pour the chocolate ganache on top of the cake, then spread to edge of cake, letting some of the chocolate drip down the sides.
12. Refrigerate for at least 2 hours before serving.