Pioneer Woman Boston Cream Pie

Directions

• Heat the milk mixture: Set a fine mesh strainer over a large measuring cup, then whisk 1 cup whole milk, 1 cup heavy cream and 1/3 cup sugar in a medium saucepan. Heat it over medium until steaming, then take it off the heat.
• Whisk the yolks: Whisk 5 egg yolks, 1/4 cup cornstarch, 1/4 teaspoon kosher salt and the remaining 1/3 cup sugar in a bowl until smooth and lemon-yellow. Drizzle in 1 cup of the hot milk slowly while whisking, so the yolks don't scramble.
• Cook the custard: Pour the yolk mixture back into the pot and whisk over medium heat. Simmer for 2 to 3 minutes, whisking constantly, until it thickens and bubbles.
• Strain and chill: Press the custard through the strainer, then stir in 3 tablespoons cubed butter and 2 teaspoons vanilla. Press plastic wrap onto the surface, let it cool for 15 minutes, then chill for at least 2 hours or overnight.
• Prep the pans: Preheat the oven to 350°F and spray two 9-inch cake pans with baking spray with flour. Line the bottoms with parchment and spray again.
• Mix the dry ingredients: Combine 1 3/4 cups flour, 1 1/2 teaspoons baking powder and 1/2 teaspoon kosher salt in a medium bowl. Set it aside while you heat the milk.
• Heat the milk and butter: Combine 3/4 cup whole milk and 1/2 cup cubed butter in a glass measuring cup. Microwave in 15-second intervals until the butter melts and the mixture steams.
• Whip the eggs: Beat 3 room temperature eggs and 1 1/2 cups sugar with a hand mixer on high speed for about 5 minutes. It's ready when pale and fluffy, so beat in the 2 teaspoons vanilla just until combined.
• Make the batter: Whisk the hot milk mixture into the eggs by hand until incorporated. Then add the flour mixture, mixing just until combined.
• Bake the cakes: Divide the batter between the pans and bake for 22 to 27 minutes, until a wooden pick near the center comes out clean. Cool in the pans for 10 minutes, then run a knife around the edges and turn them out onto a rack.
• Cool the layers: Peel off the parchment and let the cakes cool completely, about 1 hour. Warm layers would melt the filling, so don't rush this.
• Fill the cake: Place one layer on a plate, then whisk the chilled cream filling until smooth. Spoon it on, leaving 1/2 inch bare at the edge, then top with the second layer bottom side up and refrigerate.
• Make the ganache: Combine 2/3 cup chocolate chips, 1/3 cup heavy cream and 1 teaspoon vegetable oil in a glass measuring cup. Microwave at 50% power in 15-second intervals, about 1 minute, until melted.
• Top and chill: Pour the ganache over the center of the cake, then spread it to the edges with an offset spatula and let it drip down the sides. Chill for at least 2 hours before slicing, or wrap tightly and refrigerate for up to 1 day.