12" by 18" chocolate sheet cake or Lory's cake part 3

So at long last, here we are at the third part of the series that is Lory's cake. Oh what's that, maybe I didn't mention that this was a three part series? My bad. Well it is and it's time to talk about the cake! A really, really big cake, a cake that feeds a crowd with a couple of pieces to spare, a cake with a capital C CAKE!. 

Let me back up a bit - this story actually begins a year ago Christmas. I know, but bear with me. My Mom took me shopping for my gift – a sweet kitchen-shopping spree. (My Mom is the best, right?) For some reason, we decided it would be fun to go to the Win Restaurant Equipment Center. It's over in Long Island City, NYC – in case you are interested. 

This place is massive and full of all kinds of crazy things – most of which, as a home baker, I will never actually need. Think 24 to 48 cup muffin trays, a cookie cutter tray so you can cut out like 20 cookies at once (I was tempted by that one a bit), and every size of spatula or whisk you can think of. They also have some really useful things like squeeze bottles with tops and all sorts of containers… it really is a kitchen wonderland. Well, somewhere in the mist of all this, we stumbled upon a 12"x18" sheet pan. I don't know what possessed me, but I thought this would be a great addition to my tiny kitchen. This pan is gigantic and just barely fits in my oven. I can't say it was a terribly practical purchase as evidence by the fact that it sat, unused, in my pantry for more than a year. There was no deterring me at the time, however, logic be damned.

Fast forward to last month and my friend Cindy asked me to come to a surprise party for her wife, Lory. Right away I offered to make the cake. Little did I know what I was getting into (in a good way, Cindy, in a good way). The number of guests confirmed for the party grew and grew until Cindy thought we were expecting more than 50. She started to be concerned that the cake wasn't going to be enough. I saw an opportunity to try out my massive pan, that one that still sat in my pantry unused. I told Cindy of my plan to make a CAKE and she was all in. 

Now this is a big cake. A big, I can't believe I'm baking it in my little kitchen kind of cake. It is two layers and each layer I needed to bake separately. My 5-quart mixer could only handle so much and I only had one pan. It takes a bit longer to make because you have to do it one step at a time, but I'm still in the "let's not move to a bigger mixer just yet" camp.

​This is just the first layer - even if I wanted to, another layer of batter was never gonna fit.

​I learned a neat trick from a cake decorating class.  Since I was going to line the bottom with parchment anyway, I didn't bother greasing the entire bottom.  I just used an X to help the parchment stick and then greased the parchment and the sides.  And yes, that is my good friend, pan grease.

​Now this, my friends, is literally the biggest pan that could fit in my oven.  I suppose I could fit another one in there and then rotate top and bottom - I suppose.  But since I have to make the batter in two parts anyway... well, I don't make this big of a cake very often.

I like to bake my cake layers the day before I put together the cake.  One reason is to break up the work load a bit and then I am not as rushed.  Sometimes I even make the frosting a day before that.  But also, then the cake is not on a time clock - it can cool completely and then I wrap it up and put it in the fridge.  I wouldn't want to eat a cold cake necessarily - cake almost always tastes better room temp - unless it's an ice cream cake...mmm... ice cream cake... but I digress.  Cold cake is easier to handle and I break it less.  Notice I said less. Good thing there is usually frosting.  I was lucky this time and even with this unwieldy cake - no breaks.  Yay!  You just need to make sure to let the cake come back to room temp before you serve it.

​I ordered the cake topper from Etsy.  That, some edible flowers, berries, and pomegranate seeds made the decorating pretty easy.  It was really easy to do and pretty impressive if I do say so myself.

​The restaurant did a pretty fantastic job of plating the pieces.  They separated out the flowers and berries and made sure each piece had a little something.  I couldn't have done it better myself.  

​Looks like the rest of the party agreed.  This cake was a crowd pleaser and so delicious.  I knew I needed to buy that pan, it certainly came in handy for this cake.  :)

Chocolate 12

Chocolate 12" X 18" Sheet Cake

Double layer chocolate sheet cake - 12"x18". Serves up to 72 people.

2 Batch(es)
Preparation time
Cooking time



  • 1 cup boiling water
  • 2 2/3 cups (approx. 230g) dutch-process cocoa
  • 1 teaspoon espresso powder
  • 5 1/2 cups (690g) all-purpose flour
  • 2 teaspoons baking powder
  • 1 teaspoon baking soda
  • 2 teaspoons fine salt
  • 2 cups (4 sticks) unsalted butter (softened)
  • 4 cups (760g) dark brown sugar
  • 1 1/3 cups (270g) granulated sugar
  • 8 large eggs (room temp)
  • 4 teaspoons vanilla bean paste
  • 3 cups buttermilk (room temp)
Specialty Cakes
Fairly cheap


1. Position a rack in the center of the oven and preheat to 325°. Grease the bottom of the 12”x18” pan (just an X will do), the line bottom with parchment and then grease the parchment and the sides of the pan.

2. Each layer takes half of the listed ingredients. Make each layer separately unless you have a very large mixer and two pans. Begin by dividing all ingredients in half – one half for each layer.

3. Starting with first half of ingrediants: Combine the cocoa powder, espresso powder, and boiling water in a small bowl and mix until well combined. Set the mixture aside and allow it to cool slightly.

4. In a large bowl, combine the flour, baking powder, baking soda, and salt. Whisk to combine, set aside.

5. In the bowl of a stand mixer fitted with the paddle attachment, cream the butter and the sugars until light and fluffy. Add the eggs, one at a time (4 eggs per cake layer) and scrapping down the bowl between each addition. Add the vanilla, then buttermilk. (Batter will look a little grainy at this time, don’t worry, it will smooth out.)

6. Add the cocoa mixture to the batter and beat until just incorporated. Add the flour mixture to the batter in two batches. Scrape down the bowl between additions and beat until just combined.

7. Pour the batter into the prepared pan and smooth out the top with a spatula. Bake for 30 to 35 minutes. Cake layer is ready when a cake tester comes out clean. Cool in the pan for 10 minutes, then carefully turn the layer out to cool completely on a rack.

8. Once the pan is cool, clean and prepare the pan again. Repeat steps 3 through 7.

9. While the second layer is baking, make your buttercream of choice. I choose French meringue buttercream – I needed two batches of this recipe here.

To fill the cake:

1. Place the first layer on your cake board or platter. Evenly cover that layer with your first batch of buttercream.

2. Carefully place the second cake layer on top of the first. I wanted my sides to be naked so I used a little more buttercream just to make sure there wasn’t gap in-between the layers, but I scraped any extra away. If you wanted to also cover the side you would just need a bit more buttercream.

3. Top the second layer with the remaining buttercream. I created a pattern on top with my spatula but you could also make a smooth, flat layer. If desired, decorate with berries and edible flowers. I wrote a different post a few weeks ago about decorating this cake with edible flowers. Link to that post is here.

Serve cake at room temperature. Serves up to 72, depending how you cut the slices.

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Saturday, 19 September 2020