• Preheat oven to 350 degrees F. Grease the bottom of a 9 inch round springform pan and line bottom with a round of parchment. Leave sides ungreased. Alternatively, you may use two 8-inch round cake pans. The baking time will be reduced to about 28 minutes if using two pans. You'll also need less pastry cream.
• Weigh your flour and whisk it together with the baking powder and salt. Set aside. You can sift if you have time, but if you weigh it and whisk it you don't have to sift.
• In the bowl of a stand mixer fitted with the whisk attachment, beat the eggs for about 3 minutes. Continue beating for about 7 more minutes, adding the sugar a few tablespoons at a time, very gradually.
• Meanwhile. combine the butter, milk, and salt in a 3 to 3 ½ quart saucepan and heat just until mixture boils and butter is melted Add the vanilla extract and set aside.
• With mixer on low speed or by hand, mix the flour/baking powder mixture into the whipped egg mixture.
• Stir about 2 cups of this mixture (you can eyeball it) into the saucepan with the hot milk mixture, then add it back to the main mixing bowl and beat medium low until smooth (about 1 minute).
• Pour the batter into the pan, set the pan on a rimmed baking sheet and bake for about 40 minutes (check at 35) or until cake springs back when touched. Run a knife around sides of pan to loosen and let cool for about a half hour in the pan. Remove sides of springform and let cool completely. Alternatively, you can divide the batter between two 8 inch pans and bake for about 25 to 30 minutes.
• Split cake horizontally and fill with pastry cream. Put the cake in the refrigerator until you are ready to make the glaze.

Pastry Cream

• In a 3 to 3 ½ quart nonstick saucepan, off heat, whisk together the sugar, flour, cornstarch, and salt. Whisk in the egg yolks and a little of the milk and stir until well blended, gradually adding the rest of the milk.
• Set the saucepan on the stove and heat over medium low, whisking often, until hot. Start whisking continuously as the mixture heats and thickens.
• The pastry cream will thicken pretty quickly. It will go from lumpy to smooth, but you have to keep whisking it to keep it from burning, so control your heat carefully. Continue to cook and stir until 1 or 2 large bubbles break the surface (this might take a minute or two, but it helps kill the enzymes that cause thinning). Remove from the heat and whisk in the butter and vanilla. Note. If you have a deep fry thermometer, you may want to use that the first time you make pastry cream just to make sure the pastry cream hits 173 degrees F.
• Whisk the butter into the cream off heat.
• Transfer the pastry cream to a clean bowl, then whisk in the vanilla paste. Press a piece of parchment to the surface and let cool to room temperature.

Ganache Glaze

• For the glaze, combine ⅓ cup of heavy cream and 1 tablespoon of corn syrup in a 2 cup glass measuring cup. Heat in the microwave for about 30 seconds or until the cream is very hot, then stir in 4 oz of chopped semisweet chocolate. Stir until smooth and creamy. At this point it will be kind of thin, so let it cool down to a slightly thicker consistency and spoon over the cake.