homemade chocolate icing on the blog Makin' it Mo' Betta and used that instead of the tub of frosting. But if you aren't a frosting hater like me, go right ahead and use one. :)
I've changed the recipe a little (I always do) and reduced the amount of milk used so that the pudding layer is a little more thick and stable and I added 1/2 cup of sour cream to the cake mix. Doing so makes the cake more dense and moist - more like traditional Boston Cream Pie.
BOSTON CREAM POKE CAKE
slightly adapted from Makin' it Mo' Betta
1 box yellow cake mix plus ingredients to make cake (eggs, oil, water)
1/2 cup sour cream
2 small boxes instant vanilla pudding mix
3 1/2 cups milk
1 cup sugar
1/3 cup baking cocoa
1/4 cup milk
1/4 cup butter
1 tsp. vanilla
(or 1 tub of chocolate frosting)
Bake cake in a 9x13 pan according to package directions but adding 1/2 cup sour cream to the mix. Let cool slightly before poking holes evenly over surface of cake with the handle of a wooden spoon (poke all the way to the bottom of the pan).
In a medium bowl, whisk together pudding mix and milk. Beat for 2 minutes. Spread pudding evenly over cake, making sure to fill holes (there will be a thick layer of pudding on top of cake). Refrigerate at least two hours to let pudding set.
In a small saucepan, combine sugar, cocoa, and milk over medium heat and bring to a boil, stirring constantly with a wooden spoon. Boil for one minute (still stirring). Remove from heat and stir in butter and vanilla. Keep stirring to help icing cool and thicken. Spread quickly and gently over cake. Refrigerate until serving.
If using canned frosting, remove lid and foil cover. Microwave on HIGH for 10-15 seconds and stir. Spread gently over cake. Refrigerate until serving.
This cake keeps pretty well in the fridge. I made it on Saturday and we're still eating it today (Wednesday).