Bring the butter to room temperature. Mix the marmalade and heavy cream together. Lightly grease the cake pan with butter (take it from the amount in the ingredients) and dust with cocoa powder. Preheat the oven to 170℃.
Combine the chocolate and butter in a bowl. Place in a hot water bath and melt while mixing. Be careful not to let the hot water come into the bowl. If the hot water comes into the bowl, the chocolate will separate and you'll get bad texture.
Combine the egg yolks and 100 g of granulated sugar in a separate bowl, place in a hot water bath, and whip. When it becomes warm to the touch, remove from the hot water bath and whip until thick and white.
Add the marmalade cream into the egg yolks and whip some more. Next, sift the cake flour and corn starch into the bowl and mix well. You don't need to switch to a spatula; mixing with a whisk is okay.
Add the butter and chocolate to the bowl from Step 4.
Whip the egg whites in a separate bowl. Add the remaining 40 g of the granulated sugar one half at a time and whip well to make a meringue with stiff peaks.
Divide the meringue into 3 parts and mix into the batter one portion at a time.
Pour the batter into the pan you prepared in Step 1 and bake at 170℃ for 40 minutes. Reduce the heat to 160℃ and bake for 30 minutes. Please adjust the baking times and temperatures according to your oven. Let cool in the pan and then remove from the pan.
Try cutting out a paper heart, placing it on the top of the cake, and dusting powdered sugar through a tea strainer on top of the paper to create patterns.
You can use the paper you cut the heart out of to make a solid heart on top of the heart from Step 9.
Wrap up slices separately for a Valentine's Day gift.
Story Behind this Recipe
I love the combination of orange peel and chocolate, so I combined gateau au chocolat and marmalade.
You can dust the pan with cake flour instead of cocoa during Step 1 if you like. You can replace the corn starch with additional cake flour also. It will be delicious even if it's been stored in the refrigerator for a few days.