The secret is sugar syrup.
The secret is sugar syrup.
Chef Sally Schwartz
45 minutes
1 hours
Italian
Sweets & Desserts
You'll notice the quantities for the buttercream are given in grams; that's the best, most accurate way to get a good result for a confection like this. We've linked kitchen scale options below.

1 scraped vanilla bean (don’t use extract, it will change the cake’s color)
8 oz butter, room temperature
1 cup egg whites, room temperature
12 oz whole milk, room temperature
400g Sugar
170g Water
15g Corn Syrup
200g eggs
56g egg whites
7.5g salt
5g vanilla
1362g butter, room temperature
680g couverture chocolate, melted
Preheat your oven to 325°F.
Sift cake flour, all-purpose flour and baking powder, set aside.
In bowl of stand mixer, cream butter and sugar with paddle attachment at medium-high speed until white & fluffy (!8-10 minutes), scraping often.
Add salt & scraped vanilla bean.
Once butter & sugar are white and fluffy, decrease mixer speed to medium-low. Stream in egg whites ⅓ cup at a time, scraping bowl in between.
Add a third of the flours & baking powder. Mix until just blended.
Add half of the milk. Mix on medium-low until just blended. Scrape bowl. Add half of remaining flour to batter & continue to mix until just blended. Add the remaining milk. Mix until just blended & scrape bowl again. Add the last third of remaining flour. Again, mix until just blended.
Pour the batter into greased/floured 9” cake pans.
Place filled pans onto a half sheet pan & bake at 325° for approximately 30 minutes or until a toothpick comes out clean.
Cool cakes completely on cooling racks before frosting with Italian buttercream.
Add sugar, water & corn syrup to a stainless-steel pot.
Bring syrup to 248°F, measuring using a candy thermometer. Use a pastry brush dipped in water to wipe sides down, if needed.
While the syrup is cooking, whisk eggs, egg whites, and salt in a stand mixer with whisk attachment.
Once the syrup reaches 248°F, slowly stream it into the eggs. Once added, whisk on high speed until the bottom of mixing bowl goes down to room temperature.
Add butter in chunks and whip until thick.
Stream in melted chocolate until fully incorporated and frosting looks thick, fluffy, and even in color.
Frost cooled cakes once frosting is ready, or store frosting for up to two days at room temperature (see Note).