Try this for Chocolate Ermine (roux, pudding) frosting: REC: Chocolate Ermine Frosting. . .
I would add more cocoa, maybe 4 tablespoons; just a suggestion! smileys/smile.gif
Chocolate Ermine Frosting Roux Frosting
http://pastrychefonline.com/2012/08/24/1-2-3-4-cake-with-chocolate-ermine-frosting/
1 cup milk (I used whole milk)
4 Tablespoons all purpose flour
2 Tablespoons best quality cocoa powder (I used Pernigotti)*
1 cup sugar
fine sea salt, to taste
2 sticks cool butter
In a medium saucepan, whisk the flour and cocoa powder together with a small amount of your milk to form a paste.
Add the rest of the milk and the sugar to the pot and whisk over medium heat.
Add a heavy pinch of salt and taste. Adjust if necessary. The proto-frosting will be very sweet, but worry not. It will balance nicely when you add the butter later.
Bring the milk mixture to a boil, whisking constantly. Whisk for another 30 seconds to a minute and then remove from the heat.
Pour into a metal bowl to cool. Whisk occasionally until the mixture reaches room temperature. You can speed this up by refrigerating the mixture.
Fit your mixer with the whip attachment. Whip the butter until light and fluffy.
Add the chocolate mixture, a couple of tablespoons at a time, making sure each addition is incorporated before adding the next and scraping the bowl as necessary.
http://pastrychefonline.com/2012/08/24/1-2-3-4-cake-with-chocolate-ermine-frosting/