Author’s Note: As I begin baking through the 2014 season of The Great British Bake Off, I’d like to dedicate this blog post in memoriam to Luis Troyano, one of the finalists of that season. Sadly, he passed away in October 2020 at the age of 48 of esophageal cancer. In addition to being a talented baker, Luis was a graphic designer, a beekeeper and, following his stint on Bake Off, author of the cookbook Bake It Great.
When I launched My Great British Baking Challenge two years ago, I promised you, dear readers, that I would be honest about my failures as well as my successes. After all, I began this journey to learn as much as I could about baking, and I wanted my readers to learn from my mistakes also. So I start this season off with a confession — my first attempt at the eggnog filling for this Swiss roll failed.
I wanted to make an eggnog cream filling, but instead of using a tried-and-true pastry cream recipe and simply experimenting with the flavors, I thought I could add some mascarpone cheese to lighten the flavor while keeping it thick enough to hold its shape. Unfortunately, that didn’t work and, after several attempts to fix it, I ended up with a grainy, gloppy mess. So I started over.
Take two — I stuck with a traditional pastry cream recipe but swapped out the milk for eggnog. Then, to lighten it up, I folded in some whipped cream to make an eggnog diplomat cream. It wasn’t quite as thick as I had hoped for, but it was smooth and creamy and eggnoggily delicious!
Lesson learned: Don’t mess (too much) with a tried-and-true recipe. If what you need is a basic pastry cream, it’s okay to experiment with flavors, but don’t add or change so many ingredients that you end up with something other than pastry cream.
On the other hand, the pumpkin spice sponge recipe I used for this Swiss roll is one I’ve made before, so I knew it wouldn’t cause me any trouble. But I did put a twist on it by adding a baked-in design, much like some of the bakers in the Great White Tent did for this episode. I’ve experimented with making decorative Swiss rolls before (see my Instagram post here), so the technique was familiar, but I decided to keep this design simple and just make chocolate polka dots.
Basically, decorating a Swiss roll involves making a simple batter for the design and adding any color(s) you wish. I followed this recipe from SugarGeekShow.com, except I used cocoa powder instead of flour to get a dark brown color (and yummy chocolatey flavor!). Then, you transfer the batter to a piping bag and pipe your design onto a piece of parchment paper cut to fit the pan you will be using to bake your Swiss roll. After piping the design, just pop it in the freezer for 15 to 20 minutes while you make your Swiss roll batter. Once your batter is ready, you take the pan out of the freezer, spread the batter carefully over the pattern, rap it on the counter a couple times to get rid of air bubbles and pop it in the oven.
The sponge doesn’t take long to bake, so you must watch it carefully. After about 15 minutes, I checked mine to see if it would spring back when touched lightly; it needed a minute or two longer. You can also listen to your cake to tell if it’s done. When it stops “singing,” you know it’s ready to take out of the oven!
As soon mine was done, I used a paring knife to separate the edges of the cake from the side of the pan. I sprinkled it with powdered sugar, then topped it with parchment paper and a cooling rack and flipped it over. Then I removed the parchment paper from the underside, dusted it with powdered sugar, placed a tea towel over it and flipped it again so the design would be on the outside of the cake when it was rolled up. While the sponge was still warm, I rolled it up in the tea towel and stuck it in the fridge to cool while I made the filling.
Rather than go through the sordid details of my first (failed) attempt at eggnog cream filling, let me just tell you what I did the second time around. Using this recipe for pastry cream, I cut it in half but substituted eggnog for the milk. I also swapped ½ teaspoon brandy flavoring and ½ teaspoon vanilla extract for the 1 teaspoon vanilla that the recipe called for. This gave it a richer eggnog flavor, in my opinion, but you could certainly just use vanilla if you want to.
After letting the pastry cream chill, I whipped some heavy cream and folded it into the custard base, creating a light, airy diplomat cream that was a perfect filling for the spicy pumpkin sponge. After filling, rolling and decorating the Swiss roll with whipped mascarpone-cream swirls and chocolate flowers, I must say I can’t think of a more festive holiday dessert or whimsical fall treat!
Pumpkin Spice Swiss Roll with Eggnog Crème Diplomat
Sponge recipe adapted from TasteOfHome.com
Filling recipe adapted from KingArthurBaking.com
For the pattern:
For the sponge:
For the filling:
- 1½ c. eggnog, divided
- 1/8 t. salt
- 2 T. cornstarch
- 1½ t. flour
- 2 large egg yolks
- 2 T. butter, softened
- ½ t. vanilla extract
- ½ t. brandy flavoring
- ¼ t. nutmeg
- ½ c. whipped cream
- 2 oz. dark chocolate
- 2 oz. mascarpone cheese
- 2 T. powdered sugar
- ½ c. whipping cream
- To make the pattern batter, cream together 2 tablespoons powdered sugar, 1 tablespoon butter, egg white and cocoa powder until smooth. Transfer batter to a piping bag with a small plain tip. Line a 10×15-inch pan with parchment paper and grease the paper lightly with butter. Pipe polka-dot design onto parchment paper, then pop the pan into the freezer for 15-20 minutes while making the sponge batter.
- To make the sponge, use the whisk attachment of an electric mixer to beat eggs on high speed for 5 minutes. Gradually whisk in sugar until mixture is thick and lemon-colored. (It should reach the “ribbon stage,” where the batter falls back on itself in ribbons when the beater is lifted out of the bowl.) Stir in pumpkin and lemon juice. Into a separate bowl, sift together ¾ cup flour, cinnamon, baking powder, ½ teaspoon salt and ¼ teaspoon nutmeg, and fold into pumpkin mixture.
- Preheat oven to 375°F. Remove baking pan from freezer and pour rest of batter over pattern in pan. Spread batter gently to cover the pan evenly. Rap pan on counter a couple times to release air bubbles. Bake for 15 minutes or until cake springs back when lightly touched.
- When done, remove from oven and use a paring knife to cut the edges of the cake away from the sides of the pan. Sprinkle cake with powdered sugar, top with parchment paper and a cooling rack, and turn out onto rack. Carefully remove the parchment paper that was on the bottom of the pan and dust the cake with powdered sugar. Place a tea towel over the cake, top with a flat baking sheet, and flip it again so the polka-dots are on the bottom. Starting from one short end, roll the sponge up into the towel and place in fridge to cool for one hour before filling.
- For the filling, make an ice bath by placing a handful of ice cubes and a cup or two of water in a large bowl, then place a medium bowl inside the large bowl. (Make sure water doesn’t spill over into the smaller bowl.) Have a strainer handy.
- In a small pan, heat 1¼ cup eggnog and 1/8 teaspoon salt over medium heat until it begins to simmer. Meanwhile, whisk together cornstarch and 1½ teaspoon flour with egg yolks and remaining ¼ cup eggnog until smooth. Whisk some of the hot eggnog (about ½ cup) into the egg yolk mixture to temper it, then pour it through a strainer back into the simmering eggnog. Stirring constantly with a whisk, bring the mixture to a boil, scraping sides of pan occasionally with a spatula. Cook and stir for 1-2 more minutes or until thickened to the consistency of mayonnaise. Remove from heat and pour through strainer into the bowl in the ice bath. Stir in 2 tablespoons butter, vanilla extract and brandy flavoring until butter is completely melted. Cover with plastic wrap and press down so the plastic wrap touches the entire surface of the pastry cream so it won’t form a skin. Refrigerate until cool (about 2-3 hours).
- While pastry cream is cooling, prepare chocolate decorations: Chop the chocolate finely, and melt about 1½ ounces of it in the microwave at 50% power for 30-second intervals, stirring in between, until it’s mostly melted. Add the rest of the chocolate and stir until fully melted, microwaving for 5 seconds at a time if needed. Transfer to a piping bag with a fine tip (or a zip-lock bag with a small hole cut in one corner). Pipe flower shapes onto wax paper and leave to harden.
- When cake and pastry cream are both cooled completely, whip ½ cup whipping cream with ¼ teaspoon nutmeg to soft peak stage and fold into the pastry cream. Transfer cream to a piping bag with a ½-inch plain tip. Carefully unroll the cooled sponge and pipe the filling onto the sponge, starting at the end that will be the center of the roll. Do not overfill. Roll up cake again. Cover and chill.
- With electric mixer fitted with a whisk attachment, beat mascarpone till light and fluffy. Add 2 tablespoons powdered sugar and whisk until fully incorporated. Pour in ½ cup whipping cream and whisk, starting on low speed and gradually increasing until stiff peaks form. Transfer to pastry bag fitted with star attachment. Pipe a row of swirls on top of cake roll. Insert chocolate flowers so they are standing upright in the whipped cream. Chill until ready to serve.