Chocolate Fudge Cake with Peanut Butter Mousse Filling

Sorry in advance for the resolution-buster recipe I'm about to post!   My youngest turned 4 this week (hard to believe) and he'd seen a cake in a cookbook weeks ago he begged me to make.  The original recipe was filled with a vanilla cream and it did not turn out at all, so the glaze part is from that recipe (Source= Taste of Home Church Supper Recipes), but I had to find another recipe for the filling and I ended up improvising with it a little.  The end result was really good.

Cake:
Devil's Food Cake Mix- make according to directions in a 9x13 pan.  Cool completely.  Remove from pan (make sure you coat it well before pouring the batter in) and slice in half horizontally.  Fill with the peanut butter cream cheese filling, after it (the filling) has chilled at least half an hour.  Top with the glaze.

Filling:
1 cup whipping cream, chilled
10 oz cream cheese at room temp (I used 8 oz of red fat and 2 oz regular)
1 cup powdered sugar
2/3 cup creamy peanut butter

Beat whipping cream on high until stiff peaks form.  (So much easier to do this with a stand mixer).  Put in bowl and set aside.  Mix cream cheese and peanut butter until creamy and consistent.  Add powdered sugar and mix until combined.  Add whipped cream back in and mix on medium high until light and fluffy.  Chill for at least 30 minutes

Glaze:
1 cup sugar
1/3 cup baking cocoa
3 tablespoons cornstarch
1 cup cold water
3 tablespoons butter
1 teaspoon vanilla

In a saucepan, combine the sugar, cocoa and cornstarch.  Slowly mix water in.  Bring mixture to a boil.  Cook and stir for 2 minutes or until thickened.  Remove from heat and stir in butter and vanilla.  Cool to room temp before pouring over cake.