Just cut the recipe in half to do a 9" layer cake. You don't need to refrigerate this, if you'll be serving it within a day or 2. ** TIP: You may be able to find Pistachio extract at Walmart (baking aisle) or Hobby Lobby.
Copycat HEINEMANN's CHOCOLATE PISTACHIO Layer CAKE
2 boxes Triple Chocolate ~or~ Chocolate Fudge ~or~ Devil's Food Cake mix
1 box Pistachio instant pudding .............................. 6 eggs
2 TB dark unsweetened cocoa powder..................... 2 TB (dark) chocolate syrup
1 tsp. instant coffee powder....................................... 1 cup vegetable oil
1 tsp. vanilla extract.................................................... 1 tsp. pistachio extract (if you can find it)
1 cup milk (any kind ~ I used unsweetened almond milk)
Preheat oven to 350. Spray 2 9x13" pans with non-stick baking spray (containing flour). Then line the bottom of the pans w/ parchment paper and give that a quick spritz of spray too. Set aside.
Put the cake mixes, instant pudding, cocoa powder, chocolate syrup, instant coffee, extract(s) and eggs into your mixer and slowly beat together (not on high, or it will "pouf"out). Gradually add the oil (drizzle it on while mixer is on low), beating on low until it's mixed in. Scrape down the sides of the pan. ** Now, gradually drizzle in the milk (while mixer is on low) until it's mixed in. NOW, you can turn the mixer up to medium-high and beat 3-5 minutes until it's smooth throughout. (Remember there will be little bits of pistachio in there from the pudding mix.)
Spread half of the batter (as equal as possible) in each pan (make sure to get it evenly in the corners & sides ~ not higher in the center) ~ smooth it out. Bake for about 30 minutes or until cake tester comes out clean (the boxes will say 34-45 minutes, but that's too long). Cool completely on a rack before taking them out.
This gives you time to shell the pistachios and grind them (I used my food processor, but shelling took about an hour!)
PISTACHIO WHIPPED BUTTERCREAM FROSTING
2 sticks (1 cup) unsalted butter, room temperature
1 cup vegetable shortening (Crisco) ........................2 boxes PISTACHIO instant pudding
1 tsp. vanilla extract....................................................1 tsp. pistachio extract
1-2 drops green food coloring (optional)..................1/2 tsp. salt
1 cup heavy whipping cream..................................... 6-8 cups powdered sugar
about 12 oz. pistachios (salted or not) ~ need to shell them, if they're not already
In bowl of stand mixer fitted with paddle attachment, cream together softened butter, pistachio pudding and shortening until fluffy and well combined. Add the extract(s), salt and green food coloring (if using), but just a few low pulses, so they don't splash out.
Now add the powdered sugar (1 cup at a time ~ start with 6 and see if you need more later) Mix until well blended. The frosting will be very stiff at this point. Scrape down the sides.
Slowly drizzle in the heavy cream on low speed. (You should be able to tell now if you need another cup or 2 of powdered sugar). Once it is fully mixed in, increase the speed to high and beat for 5-7 minutes, scraping down bowl occasionally. It should be somewhat thicker than whipped cream (so the top layer doesn't weigh the filling down).
Put the bottom layer upside-down on a rectangle cake board (or platter). (The reason this layer is upside-down is so that the flat bottoms of both layers are together in the center ~ making an even layer of Pistachio Buttercream Filling)
(TIP 1: I spread some canned frosting on the cake board first, which acts as "glue", so the cake won't slide if you're transporting it somewhere. Any flavor is fine). (TIP 2: Put strips of waxed paper under all sides of the cake to catch any drips of frosting ~ then slide them out much later when everything is set.)
Spread a thick layer of Pistachio Buttercream (at least an inch) evenly over the bottom layer. Put the top layer on (rounded side up). Now, put a very thin coat of frosting all over the sides and about 2" onto the top edges of the cake. (This is your "crumb coat" ~ Let it set for about 5-10 minutes, to seal any loose crumbs, so they won't show through when you finish frosting your cake.) Now, you can go back and just slather that frosting all over the sides and about 2" in on the top of the cake (CHOCOLATE GANACHE will go in the center). Really, just use it all up and put it all on there!! ** Now, the tricky part is get the finely chopped pistachios on the side of the cake. I stuck my rubber scraper in the bowl of pistachios and just laid it next to the cake (yes, some will fall down but you have waxed paper down there, and can just scrape them up and use them). Whew!! Let your cake rest (while you rest too), before you put warm ganache on top. ...
about 1/4 to 1/2 cup heavy cream ~or~ milk ~or~ liquid coffee creamer
about 8-12 oz. chocolate (I used semi-sweet, but dark is good too) ~ baking bars, chips, melting wafers
Put whatever your liquid is, into a glass bowl with your chocolate and put into the microwave for 1 minute. Now, stir with a spoon (or use a whisk) until the chocolate is all melted and it's shiny & smooth. If it's too thick, add a little drizzle of your liquid while you're stirring. If it isn't thick enough, add a little more chocolate. (If the added chocolate doesn't melt, you may need to put it back in the microwave another 30 sec. or so.) This will actually keep in a covered glass dish in the fridge for about a month (adding more liquid or more chocolate as needed). *** But, back to the cake!! Spoon the slightly cooled CHOCOLATE GANACHE into the center of the cake (you should have "barriers" on top of frosting).
TIPS & HINTS: After a while, it may seem like the filling is coming out of the layers, but the frosting sets well, and you can "smash" it back in (lightly) with the back of a metal spatula or your rubber scraper (or even the palm of your hand). Just ignore it for a few hours, and it should be pretty-well set, so you can gently even up those sides with the spatula. You can gently pull out the waxed paper now too.
FOR SUGAR-FREE: Substitute sugar-free chocolate cake, sugar-free pistachio pudding mix and use sugar-free chocolate syrup (all the other add-ins are fine). The powdered sugar is trickier but you can sift together 3/4 cup regular blend Splenda with 1/4 cup cornstarch (that makes 1 cup ~ so you'll need to LOTS of that) *** or just use a couple of cans of sugar-free canned vanilla frosting, beating in heavy cream and sugar-free pistachio pudding mix. *** Use sugar-free chocolate chips for the CHOCOLATE GANACHE.