Recipe video (my You Tube channel)https://youtu.be/VEpoP1MR4DA
Preheat an oven to 190 / 374F. Sift cocoa powder; set aside. Put unsalted butter a heat-resistant bowl; set aside.
Put couverture chocolate in a bowl. Bring water to a boil and then turn off the heat. Put the bowl with chocolate on the top of the pot so as not to touch the hot water directly.
Wait for 30 sec and then melt the chocolate until smooth. Remove the bowl and let it cool. Put the bowl with butter in the hot water to melt it; set aside.
Prepare hot water to warm egg mixture (low heat). Put an egg and an egg yolk in a large bowl. Beat it lightly with a whisk until watery. Add granulated sugar and stir well.
Warm the egg mixture in the hot water until it reaches body temperature while stirring. Take the mixture off from the hot water. Whip the egg mixture with a hand mixer on high speed until whitish and heavy.
Add the chocolate to the egg mixture in 3 parts. Stir well with a whisk until combined. Pour the butter and stir well until smooth.
Sift the cocoa powder over the batter. Stir well. Add brandy and vanilla oil. Scrape off the batter with a spatula on the inner side of the bowl. Mix well until combined.
Transfer the cake batter into a piping bag. Line muffin mold with glassine paper. Pour the cake batter into each cup. Bake it at 170 / 338 F for 25 mins. (I put the muffin mold on the net so that the bottom of cake can be baked through.)
Let it cool as it is. They will shrink slowly. Take each cake off from the mold. Done!! It's also delicious to eat with lightly whipped sugar-free heavy cream or after chilling in a fridge. When you chill it, please wrap with plastic wrap so as not to dry.
