Over the weekend, Andy commissioned me to make a cake to celebrate the birth of a coworker’s son. He gave me no constraints and no specific criteria, so I had the free reign to decide the design. I’ve been loving ombre lately, and when I saw this blue ombre cake I knew I had to recreate it!
The cake is a genoise sponge cake soaked with champagne simple syrup and frosted with an Italian buttercream. One of the reasons I love baking at home is because I can practice techniques I’ve learned at school but get a bit more creative with the design.
And since I tend to complicate things I made three different batches of genoise, each tinted a different shade of blue. It definitely increased the time I spent making the cake but it is totally worth the overall effect!
(The cake layers above appear to have a slight green tint because of the browning in the oven.)
Yield: fills ~1/2 of an 8” cake pan
3.45 oz eggs
2.25 oz sugar
2.25 oz flour
.75 oz vegetable or canola oil
Line 8” cake pans with 8” parchment round. Do not grease pan. Preheat oven to 350°F.
Combine the sugar and eggs in the bowl of a stand mixer. Add gel food coloring for desired color, remembering that the color will lighten significantly as the eggs are whipped. Over a water bath, heat the eggs and sugar to 110°F while whisking.
Remove from water bath and put in stand mixer fitted with whisk attachment. Whisk on high until the mixture reaches its maximum volume, about 15 minutes. It has reached its maximum volume when the whipped eggs have receded slightly from the highest point on the bowl. Reduce the speed to medium and whip for an additional 15 minutes.
Transfer the whipped eggs into a shallow bowl (folding in a stand mixer bowl is difficult, as flour tends to accumulate on the very bottom). Sift about 1/3 of the flour over the top of the eggs and fold to combine. Repeat this process 2 more times until all of the flour is incorporated.
Remove a small scoop of the whipped egg and flour mixture and stir into the bowl of oil. Once well mixed, add it to the whipped eggs and fold to incorporate. This tempering allows the oil to be added into the eggs without deflating the fragile mixture.
Pour the mixture into the prepared cake pans. Bake for 20-25 minutes, or until the genoise has pulled away from the edge of the pan and springs back when touched.
Let cool fully. Run a paring knife around the edge of the genoise to release the cake. Turn out onto 8” cardboard.
Champagne Simple Syrup
Yield: 8 oz
4 oz champagne
4 oz sugar
Combine the sugar and champagne in saucepan. Bring to a boil and remove from heat. Set aside and cool until ready to use.
I used Cuveé M from Mumm Napa. From wine.com, “The aromas are elegant, rich and complex, showing fresh white and yellow stone fruits with subtle hints of wild strawberry. A light touch of fresh brioche, with hints of vanilla and honey add to the wine’s complex bouquet. On the palate, full flavors of peach and pear combine with a creamy caramel character, which lingers into a long satisfying finish.”
Yield: 3 pounds*
8 oz egg whites
16 oz sugar, divided
4 oz water
1 lb 8 oz butter, room temperature, in 1” cubes
In the bowl of a stand mixer, combine 8 oz egg whites and 4 oz sugar. Set aside.
Combine remaining 12 oz sugar with water in saucepan fitted with candy thermometer. Heat the sugar and water, without stirring, to 230°F. When the mixture reaches 230°F, turn the mixer to the highest speed and beat the egg whites to medium peaks.
Continue heating the sugar to 242°F. When the sugar has reached this temperature, decrease the mixer’s speed to medium. Slowly stream the hot sugar into the egg whites, taking care to stream the sugar between the side of the bowl and the whisk attachment.
Once all of the sugar has been added, whip the mixture on high until cooled. Reduce the speed to medium and add the chunks of butter.
Divide into thirds. Use gel food coloring to create desired shades. Fill piping bags fitted with #12 tip. The two orange bags are Fat Daddio’s silicone pastry bags, which I absolutely love!
* I had about 1 to 1.5 cups of frosting left over.
Place the darkest color genoise onto a rotating cake stand. Using a pastry brush, saturate the surface of the genoise with the champagne simple syrup. Put a large scoop of buttercream onto the cake layer and smooth with flat spatula. Add second layers, following the same steps of adding simple syrup and frosting.
Once the three layers are assembled, frost the sides with a thin layer of buttercream. This initial layer of frosting traps the crumbs and ensures a clean top layer, hence the name crumb coat. Place the cake in the refrigerator or freezer until crumb coat is solid.
Pipe small circles in a vertical line onto the side of the cake. Using an offset spatula, smear the circle to the right to create the petal appearance. Continue piping vertical rows of circles and pulling the circles to the right. There is a great tutorial for this technique here. To finish the design, pipe a row of small circles and do not smear them.
Finish the cake’s edge by piping shells using a small start tip.
Using the same method, pipe the top of the cake.