If you've ever had a piece of Boston Cream Pie, then you already know that it's not a pie at all, it's a cake...and a delicious one, at that! Confused? Don't be...that's just the way it is. Heehee! It's filled with vanilla custard or cream, and frosted with chocolate. It's just heavenly!
1For Vanilla Cream:
Combine flour, sugar, salt and eggs in saucepan and stir until smooth; gradually add milk and continue to stir constantly over medium heat, until thickened. If it looks lumpy, use a wire whisk and it will smooth out nicely. Add vanilla and butter after pudding has thickened. Store in refrigerator until ready to use. (Hide it from the kids, mine would eat it while it was still warm. Yes, it's that good!)
Heat the oven to 350°F. Spray just the bottom of a 9-inch round cake pan with the baking spray.
3In a large bowl, beat all cake ingredients with an electric mixer on low speed 30 seconds, stopping frequently to scrape batter from side and bottom of bowl with a rubber spatula. Beat on high speed 3 minutes, stopping occasionally to scrape bowl. Pour batter into the pan; use a rubber spatula to scrape batter from bowl, spread batter evenly in pan and smooth top of batter.
4Bake about 35 minutes or until a toothpick inserted in the center comes out clean. Cool cake in pan on a cooling rack 20 minutes, then remove onto cooling rack to finish cooling completely, about 1 hour.
5For Chocolate Icing:
In a 1-quart saucepan, melt 3 tablespoons butter and the chocolate over low heat, stirring occasionally. Meanwhile, in 1-cup glass measuring cup, microwave the water uncovered on High 15 to 30 seconds or until hot. Remove chocolate mixture from heat. Stir in the powdered sugar and 3/4 teaspoon vanilla. Stir in 3 tablespoons hot water. Stir in additional water, 1 teaspoon at a time, until icing is smooth and thin enough to spread.
To split cake horizontally in half, mark middle points around side of cake with toothpicks. Using toothpicks as a guide, cut through the cake with a long, sharp knife, using a back-and-forth motion. On a serving plate, place bottom layer with the cut side up. Spread filling over bottom layer. Top with top of cake, cut side down.
7Spread glaze over top of cake, using a metal spatula or back of a spoon, letting some glaze drizzle down side of cake. (I top mine with a cherry in the middle, but you don't have to do that.) Refrigerate uncovered until serving. Store any remaining cake covered in the refrigerator.