After the strawberry chocolate cake fiasco that wasn’t, I think I’ve been bitten by the gourmet cake making bug. One step closer to my burgeoning career-slash-dream job as a wedding cake baker in another life, I guess? But alas, in this life, I’m stuck with muddling through endless Powerpoint slides on circuits and Newtonian fluid dynamics instead of border piping technique. I suppose it’s all for the best – while it’s perfectly possible to be a doctor who makes fancy pastries on the side, I imagine it might be a little tricky to be a pastry chef who dabbles in doctoring on the side.
Speaking of medical school, while I have been repeatedly assured that I will develop a taste for every working professional’s stimulant of choice sometime during those four years, I still haven’t hopped onto the coffee train just yet. My version of a caffeinated beverage is not so much cream and sugar in my coffee as it is coffee in my cream and sugar. Fortunately, that’s more or less exactly what espresso mousse is, so when Dad asked for a vanilla coffee layer cake for his birthday, I grabbed (the very last!) package of vanilla beans from Costco and copious gourmet chocolate covered espresso beans from Fresh Market and hopped to it.
The best part of vanilla beans, as I quickly learned, is that while they are $1.60 apiece even in bulk, each bean goes a long way. This recipe only technically uses half of the seeds scraped from the pod – you dissolve all the seeds in 1 cup of milk, but freeze half of the batch for another day. You’re also left with an entire bean pod, which can be cut into quarters and dropped into a jar with 2 cups of sugar – shake well every 20 minutes for an hour, then let the jar sit for a delightfully potent vanilla sugar. I ended up using some of the vanilla sugar in the vanilla chiffon cake instead of using vanilla extract, and still had about 12 oz leftover for a rainy day. Make the most of those pricey beans!
As for the other type of beans in this week’s cake, I grabbed about 4 ounces of assorted chocolate-covered espresso beans from the bulk section of the Fresh Market closest to my house. (Incidentally, I also picked up a bag overpriced gourmet trail mix, which I am probably excessively fond of considering it was my primary source of stress eating subsistence for about 7.5 hours while I took the MCAT.) If you lay them down just right and play around with them a bit, they fit quite neatly against each other to make a sort of wavy cobblestone/mosaic border around the bottom of the fully frosted cake. Also, it’s just incredibly satisfying for any internal obsessive-compulsive tendencies in the same way as a perfect row in Tetris.
Aside from the vanilla chiffon cake, which is a little out of the ordinary but nothing to bat an eye at, and a fairly run-of-the-mill espresso mousse filling, I deviated from the typical vanilla bean buttercream to frost this week’s cake with vanilla creme diplomat, which is just a mixture of pastry cream and whipped cream. It makes for a much lighter frosting than your standard American buttercream (or even German buttercream, which is basically pastry cream with whipped butter), making it a stable (unlike plain whipped cream) but still generally fluffy complement to the equally fluffy interior. After a pretty but messy affair last year, I quickly discovered that creme diplomat makes for a much friendlier spackling agent for an easily squishable cake like chiffon.
So whether you’re the type to fantasize about a black coffee IV drip or merely dabble in what could generously be called coffee-flavored milk, there’s something for everybody in this vanilla espresso cake (even if you’re just in it for the chocolate, which is also completely okay). Give it a try, and hope you enjoy!
Vanilla Espresso Cake
Makes one 4 layer 6″ cake
Vanilla Chiffon Cake:
120 g (1 cup) all purpose flour
7 large eggs, separated into yolks and whites
1/4 cup vegetable oil
1/4 cup milk, any type
3 tbs + 7 tbs vanilla sugar, separated
Espresso Mousse Filling:
1/2 cup milk
1 1/2 tbs instant espresso powder
1/4 cup granulated sugar
1/2 tbs gelatin powder
1 cup heavy cream
Vanilla Creme Diplomat Frosting:
1 cup milk
1 vanilla bean pod, cut in half and scraped for seeds (or 2 tsp vanilla extract)
1 egg yolk
2 tbs granulated sugar
20 g all purpose flour
1 cup heavy cream
Assorted chocolate covered espresso beans
White writing icing (1/4 cup powdered sugar + 2 tbs shortening + 1 1/2 tbs milk)
Vanilla Chiffon Cake:
- Preheat the oven to 350 °F and lightly grease your baking pans.
Tip: I used four 6″ layer cake pans (plus just enough extra batter for a cupcake), but you should be able to divide the mixture into two 9″ round cake pans to a make a shorter, wider cake.
- Beat the 3 tbs of sugar into the egg yolks until well mixed, then beat in the vegetable oil and milk.
- Sift in the flour in 3 additions (add in 1/3 of the flour at a time), gently whisking in just until no visible dry clumps remain. Set the mixture aside.
Tip: Especially after the first two additions, you will still see lumps in the batter after the dry, white clumps are mixed in. That’s okay! It’ll more or less smooth out after the third addition, and any lumps should be small enough not to make a difference once the cake is baked.
- Place the egg whites into the bowl of a stand or electric mixer and start whipping at a slow/medium speed. While the egg whites are still foamy, add the remaining 7 tbs of sugar in 3 additions about 20-30 seconds apart. After the third addition, whip the egg whites on high until the stiff peaks stage.
Tip: When the egg whites are fully whipped, the mixture should be glossy and you should be able to lift the beaters out to leave a sharp standing peak behind that does not bend over.
- Add 1/3 of the whipped egg whites into the egg yolk mixture, gently folding in the whites until just until no large lumps remain.
- Pour the mixture into the remaining 2/3 of the whipped egg whites and gently fold together just until no streaks remain.
- Divide the batter into your cake pans and bake for 18-20 minutes for the 6″ cakes or 28-30 minutes for the 9″ cakes, or until an inserted toothpick comes out clean.
Tip: This cake will puff up as it bakes, but shrink right back down to the original size once it cools, so go ahead and fill the pans to the brim if you can — don’t worry about leaving room at the top of the pan for the cake to expand!
- Set the cake layers aside to cool!
Tip: After the layers are reasonably cooled, feel free to stack the layers, separating with parchment paper, for easier storage while you prepare the buttercream.
Espresso Mousse Filling:
- In the microwave, warm the milk in 20 second intervals the mixture is slightly warm to the touch. Mix in the espresso powder and sugar until fully dissolved.
- In a shallow dish, add about 1/3 of the milk mixture to the gelatin powder and set aside for 10 minutes, or until the gelatin fully hydrates and becomes completely transparent.
- Microwave the gelatin in 10 second intervals until the gelatin fully melts, then add the melted gelatin into the remaining 2/3 of the milk mixture, stirring until fully combined. Set aside to cool completely.
- In the bowl of a stand mixer or with an electric mixer, whip the heavy cream until it reaches stiff peaks. At this point, when you lift out the whisk, you should see distinct peaks with tips that do not curl over. Fold in the cooled espresso mixture until fully incorporated, then place in the refrigerator to chill until you are ready to assemble the cake.
Assembly, part 1:
- Place one layer of the chiffon cake in the center of a large, flat plate.
- Create a collar mold for the cake:
- Cut a long strip of poster board with a width that is about 6x the height of the cake layers.
- Wrap the strip around the cake layer to create a cylindrical collar that fits snugly around the bottom of the cake. Tape to secure.
- Line the inside of the collar with parchment paper, taping to secure.
- Place the collar around the bottom layer of the cake to form a tall cuff to serve as a mold.
- Add a generous layer of espresso mousse on top of the chocolate cake. Use a metal spatula to smooth out the mousse into a flat, even layer.
- Top with the next layer of chiffon cake, and continue adding alternating layers of cake and espresso mousse, ending with the 4th chiffon layer.
- Chill the cake in the refrigerator for at least 1-2 hours to set the mousse.
Vanilla Creme Diplomat Frosting:
- Heat the milk and vanilla bean seeds in a small pot on medium-high heat until the liquid comes to a boil. Turn the heat down to medium-low. Set aside half of the vanilla milk for another recipe.
Tip: The vanilla milk freezes really well in an ice cube tray!
- Whisk together the egg yolks and sugar in a bowl until the sugar is nearly fully dissolved and the egg is frothy. Whisk in the flour and set aside.
Tip: After adding the flour, your mixture will be very pasty and thick. Don’t worry – that’s exactly what it ought to be!
- Pour in about 1/2 of the remaining boiling milk mixture into the egg mixture, whisking quickly as you pour.
- Pour the egg mixture back into the pot through a sieve, whisking quickly as you pour. Continue whisking until the pastry cream thickens to the consistency of thick pudding, then remove from heat.
Tip: Always make sure to mix your eggs into the milk by tempering them with hot milk, then pouring through the sieve rather than dumping them all in at once. No matter how many times and how quickly I’ve tried to whisk while pouring in untempered eggs, I always ended up with unpleasantly eggy pastry cream because some of the egg inevitably scrambles as it hits the hot milk. After lots of sadness, disappointment, and wasted pastry cream, I finally started to use this tempering method as a virtually fool-proof strategy for keeping pastry cream (or any other type of custard) scrambled eggs-free!
- Pour the mixture into another bowl, cover the surface with saran wrap, and set aside to cool completely.
Tip: Make sure the saran wrap touches the surface of the pastry cream when you cover the bowl to prevent a skin from forming at the top of your pastry cream if the surface dries out.
- In the bowl of a stand mixer or with an electric mixer, whip the heavy cream until it reaches stiff peaks. At this point, when you lift out the whisk, you should see distinct peaks with tips that do not curl over.
Tip: It is very important to make sure that your cream reaches stiff peaks, or else the creme diplomat will not hold when you frost! That said, make sure to stop as soon as you hit stiff peaks, or else you will start churning butter instead of whipped cream.
- Beat the cooled pastry cream to loosen, then fold in 1/3 of the whipped cream at a time until fully incorporated. Load into a piping bag with a large round tip (I used the Wilton 1A!), then set aside for filling!
Assembly, part 2:
- Remove the cake from the refrigerator and gently peel off the paper cuff.
- Using a large offset metal spatula, frost the cake with the vanilla creme diplomat, smoothing around the sides before leveling the top.
- Arrange a mosaic of chocolate covered espresso beans around the sides of the cake, starting from the bottom, to form an asymmetric wavy border.
- Dust the entire top of the cake with cocoa powder. Pipe small swirls of whipped cream around the top of the cake, dust again with more cocoa, and top with dark chocolate espresso beans.
- Load the icing into a piping bag fitted with a small round tip, then pipe on your message of choice.
Tip: Unfortunately, cocoa powder is not the most conducive surface for writing neat, tidy messages the first go around. Fortunately, it is conducive to finagling your finished icing product with toothpicks to stretch and otherwise generally rearrange the icing until it looks the way you like – just tug gently with the tip of the toothpick to slide the icing around on the dry cocoa.
- Chill until you are ready to serve. Enjoy!