1. Prepare the cake. Preheat oven to 350 degrees F. Spray a 9-inch round baking pan with vegetable cooking spray.
2. In a large bowl, use an electric mixer on medium-high speed to beat butter until fluffy, about 2 minutes. Add sugar and beat until light and fluffy, about 2 minutes. Add 1 egg and beat 2 minutes on medium-high speed. Scrape side of bowl and add vanilla, beat 1 minute, scrape sides, and add remaining egg. Beat for 2 minutes until mixture is very light.
3. In a separate bowl, stir together flour, baking powder, baking soda, and salt. Add 1/3 of the flour mixture to the butter mixture and blend on low speed just until incorporated. Scrape down sides and add half the buttermilk, mixing on low just until blended. Add another 1/3 of the flour, mix, then remaining buttermilk, mix, and finally, remaining flour, mixing just until smooth. Batter will be thick. Transfer to the prepared pan, smoothing the surface.
4. Bake until the surface is lightly golden and springs back when lightly touched, and a toothpick inserted in the center comes out clean, about 33 to 38 minutes. Be careful not to overbake. Cool cake in the pan on a wire rack to room temperature, about 1 hour.
5. While cake bakes, prepare the pastry cream. In a medium bowl, gently whisk together egg yolks, milk, cream, rum, and vanilla.
6. In a medium saucepan, stir together sugar, cornstarch, and salt. Stir in milk mixture to blend. Bring to a boil on medium heat, stirring constantly; mixture will start to thicken in about 7 to 9 minutes. Boil for 1 minute, continuing to stir constantly; mixture will be thick and pudding-like. Remove from heat and pour custard into a sieve set over a bowl. Use a spoon or spatula to press mixture through sieve to smooth out any lumps. Press plastic wrap against the surface and cool to room temperature, about 30 minutes, then refrigerate until ready to use (may be prepared a day in advance).
7. Assemble dessert. Run a knife around the edge of the pan and gently invert cooled cake onto a work surface. Using a long serrated knife, slice the layer horizontally into 2 rounds. Place the bottom round on a serving plate, cut-side up. Spread reserved pastry cream over the surface, then place second layer on top, cut-side down.
8. Prepare the chocolate glaze. In a small saucepan over low heat, melt chocolate and butter together, stirring to blend. Pour glaze over top of cake and use a butter knife or spoon to spread it just to the edges so some drips down the side. Let chocolate set completely, about 30 minutes, then slice and serve. May be stored at room temperature for 1 day, or in the fridge.
Source: Hannaford fresh Magazine, September - October 2015