• Preheat the oven to 350°F. Prepare three 9-inch and three 6-inch cake pans by lining them with parchment circles, but nothing else. The batter needs to grab the sides to rise in the oven and to successfully hang upside down to cool.
• In a large bowl, whisk together the flour, 2 cups (400 grams) of the sugar, the baking powder, and salt. Set aside. In a separate bowl, stir together the egg yolks, oil, coffee, and vanilla.
• Add the dry ingredients to the yolk mixture and mix together with a rubber spatula until smooth. Set aside.
• In a stand mixer fitted with the whisk attachment, combine the egg whites and cream of tartar and beat on high speed until medium peaks form, about 2 minutes. Turn the speed to medium-low and slowly sprinkle in the remaining 1 cup (200 grams) sugar to create a French meringue. Turn the speed to high and beat until stiff, glossy peaks form, 1 to 2 minutes more. Using a rubber spatula, fold the meringue into the batter a third at a time.
• Divide the batter between the ungreased pans. Use an offset spatula to smooth and run the spatula through the batter to release any large air bubbles. Bake until the cakes bounce back to the touch and a tester comes out clean, about 18 minutes for the 6-inch rounds, and 20 to 25 minutes for the 9-inch rounds. Immediately invert the pans onto wire racks and let rest to prevent the cakes from compressing. Leave upside down until completely cool, about 45 minutes.
• Using a paring knife, very carefully loosen the cake away from the edge of the pan and the center. Invert the cakes onto cardboard rounds.
• When ready to assemble the cake, level the cake layers by cutting off the tops of each layer. Place the bottom 9-inch cake layer on a serving plate or cake stand. Spread a 1/4-inch layer of the Coffee Whipped Cream on top. Add a layer of 1/2-inch pieces of Honeycomb Candy. Cover with another layer of whipped cream. Place the second 9-inch cake layer over top. Repeat layers and top with the third 9-inch cake layer. Place the first layer of the 6-inch tier on a 6-inch cardboard round and assemble the layers just like the 9-inch tier, layering the whipped cream and candy. Smooth the sides of each cake. Cover each cake with plastic wrap and refrigerate it overnight. This allows the honeycomb candy to soften for easy cutting.
• When ready to finish, frost the entire 9-inch cake tier with Espresso Buttercream and use an offset spatula or knife to smooth it out. Place in the refrigerator while you frost the 6-inch cake tier.
• To assemble the tiered cake, cut extra large straws or plastic cake dowels and cut to exact height of the 9-inch cake tier. Push the straws directly into the cake, positioned evenly around the cake within the 6-inch circle, to provide strength to hold the second tier. Place the frosted 6-inch tier with the cardboard round, directly on top of the 9-inch cake tier, using the straws as the foundation for supporting it. Decorate the cake with pieces of honeycomb candy and top with flowers for decoration.

Coffee Whipped Cream

• In a medium saucepan, bring the cream, broken coffee beans, and sugar to a simmer. Turn off the heat and allow to steep for 15 minutes. Strain the mixture and refrigerate for at least 2 hours.
• When ready to decorate the cake, in a stand mixer fitted with the whisk attachment, whip the coffee-flavored cream on medium speed until just stiff (do not over beat). Use immediately.

Honeycomb Candy

• Line a baking sheet with a silicone mat. In a large pot, heat the sugar, coffee, and corn syrup without stirring until the mixture reaches 302°F on a candy thermometer. Immediately remove from the heat and stir in the baking soda. It will foam up as you stir. Quickly pour it into the prepared pan. Allow to cool completely. Remove from the pan and break into pieces. The candy will keep for 3 to 4 days at room temperature in an airtight container.

Espresso Buttercream

• In a stand mixer fitted with the paddle attachment, combine the confectioners’ sugar and butter and beat on low speed until combined. Turn the mixer speed to medium and beat until a thick paste forms. Scrape down the bowl and paddle.
• In a small bowl, dissolve the espresso powder in the vanilla extract. Add the vanilla-espresso mixture and salt to the butter mixture and beat for a few seconds more. With the mixer on low speed, add enough of the cream, 2 tablespoons at a time, to make the frosting spreadable. Use immediately.