Recently, I had the pleasure of working with my favorite baking company, King Arthur Flour. Every year they choose a recipe they dub “recipe of the year” and it’s always foolproof and absolutely fabulous. Last year’s was a banana bread which I still make every time my bananas go ripe (in fact I might be doing that today…). This year the chosen one is a tender yellow cake topped with a super chocolatey buttercream, KAF’s take on the Classic Birthday Cake and, really it is divine! I turned their recipe into a sheet cake and wanted to use the photos from the shoot I did for them to talk generally about making really great sheet cakes which have become a bit less popular in the years of pinterest-pretty layer cakes. This post isn’t sponsored, I just think sheet cakes are fantastic for parties and large gatherings: they are easy to decorate, cut and serve. I also think they make a beautiful canvas for a creative background (like I did for this Sunshine Cake or my Cherry Blossom Cake) and in an effort to lobby for returning them to popularity, I’ve put together some tips on baking and decorating them. Some of the tips are applicable to any cake, some specific to sheet. Each adds a little more expertise to your baking arsenal, and gets you closer to the cake you aspire to serve!
* Converting a layer cake recipe to sheet: If a given recipe is for two 8” round cakes, this is enough batter to fill a sheet pan. If your recipe is for three 6” round cakes, increase the batter by one third to fill the sheet pan.
*Room temperature eggs: a quick way to get eggs to warm up is to put them in a bowl with hot water. In just a few minutes they’ll be the perfect temperature.
* Bowl scraping: this doesn’t get said enough. Every time you move from one step to another to add more ingredients, be sure to scrape your bowl to ensure every part of the batter get’s combined. If you don’t, you’ll have pockets of unmixed batter in your final cake.
* My worst fear is a cake that sticks to the pan, I use a flour+butter spray to prevent sticking on any cake batter. With a sheet pan I also add parchment paper - but just on the bottom. The cake is so big you’ll want to ensure it doesn’t break in the bottom middle when you turn it out.
* Once it’s out of the oven, let the cake sit for about 15 minutes in the pan, then invert it onto a cooling rack. You don’t want it getting too comfy in the pan because it will start to sweat.
*Organic powdered sugar: I always recommend using organic powdered sugar in recipes where the sugar won’t be cooked. In the organic variety, tapioca starch is used which melts on the tongue. It’s usually clumpier and will need to be sifted, but it’s well worth it. It can be expensive but buying in bulk via amazon is a very affordable option.
* Beat the butter before adding the rest of the ingredients: doing this will give you a fluffier buttercream.
* Smooth the buttercream onto a sheet pan with a small offset spatula and use the spatula to create swirls. There’s no real method for doing this, but be gentle but firm and think of the letter “S” as you move your hand.
*First you’ll need to melt a chocolate of your choosing (this is my go to), by tempering it. This guide via KAF offers some solid methods for tempering chocolate. Basically, you want to do it slowly over a double boiler (or a heatproof bowl over a pot of gently simmering water, ensuring the bowl doesn’t touch the water).
*If you plan to serve it in the pan you baked it, frost it once it’s back in the cooled pan (remember we took it out to cool!).
*It can be hard to find serving options other than the pan it was baked in because of the size but here are a few options: an upside down cookie sheet pan, straight on parchment paper, or a chopping board.
* The greatest thing about sheet cakes is how easy it is to serve them compared to layered cakes which are more prone to uneven slices, and usually collapse halfway to the plate. None of that is an issue here which makes sheet cakes a fab choice for larger parties! Cut them however you like, even squares or longer rectangles - or you can even use deep round cookie cutters to serve mini cakes!