Break the chocolate into small pieces and put in a heat-proof or microwavable bowl. Place the bowl in a slightly larger pot with water to create a water bath and heat the pot over medium to low heat until chocolate is melted. Make sure the bowl does not touch the bottom of the pot! Alternatively, you can heat the chocolate at short intervals in the microwave (30 seconds to 1 minute at 500W). The microwave melting is a bit trickier, as you could accidentally burn the sugar in the chocolate which causes small lumps in the sugar and a weird taste. I, therefore, recommend using the water bath method to melt your chocolate! Set your melted chocolate aside to let it cool a bit.
While your chocolate is cooling down, separate the egg whites and egg yolks. Make sure to not transfer any egg yolk bits to your egg white, otherwise you won’t be able to beat them up later. I recommend breaking them into small bowls first before adding them to a larger bowl or pitcher. Set your eggs aside for now.
Preheat your oven to 170°C or 340°F. Grease one high 9-inch springform pan or 2 regular 9-inch layer pans and lightly dust with flour. Set aside.
Beat the butter with your powdered sugar and vanilla extract until pale and creamy. Stir in the egg yolks, one by one, incorporating each well before adding the next. Slowly add the melted chocolate and keep on whisking until fully incorporated. Next, you guessed it, set aside for now!
In a separate bowl, beat the egg whites with the salt using an electric mixer (you could do this by hand, but it will really take a loooong time!) until frothy. Gradually add the sugar and keep beating until you get a light and fluffy egg white cream. You know you’re ready when you can flip the bowl upside down and nothing drips out. (Leaky Egg Whites are not covered by the AFM Warranty).
Time to mix everything together! Fold in one half of your egg whites to the mix, slowly incorporating it (don’t stir too much!). Fold in one half of your flour and carefully mix as well. Repeat this both for the remaining egg whites and the flour. Pour your dough into your prepared pans and bake for about one hour or until a toothpick inserted into the center comes out clean. Take out your cake and let it cool completely. Cut it lengthwise in half using a large knife or a handy cake saw as I have!
Stir your apricot jam to create a smooth paste. If it is too hard, you can put it in the microwave for a few seconds before stirring. Liberally spread the jam on one half of your cake. Put the second half on top and brush the entire outer area of the cake with apricot jam as well. Put the cake into the fridge to set.
Time to make the glaze! Put the water and sugar into a pot. Heat over high heat until boiling then reduce heat to medium and let it boil for about 3 minutes. Take away from heat and let it cool down for about 5 minutes. Slowly add the chocolate and keep on stirring until you get a nice shiny chocolate glaze. If your chocolate isn’t melting, you can reheat the mix over very low heat and keep on stirring until it is smooth. Let the glaze cool, stirring occasionally. You know that you’ve reached the right temperature when the glaze almost feels cold on your lips (yes, this means you get to test your glaze every now and then by smearing a small bit on your lips!).
Take the cake out of the fridge and put on a raised cooling rack. Place some parchment paper beneath your cooling rack. Boldly pour the glaze over your entire cake and spread with a large palette knife if necessary. Let the glaze harden. You can speed up the process by putting the cake in the fridge. If the cake has been thoroughly cooled down, the glaze will harden in about 10 minutes. Enjoy!