1. Preheat the oven to 350 F and position the oven rack in the middle.
2. In a food processor, add 350 g of white sugar and pulse until fine.
3. Remove 190 g of sugar from the food processor and set aside to use with the egg whites.
4. To the remaining sugar in the food processor, add 130 g of cake flour and salt. Pulse 5-10 times. Set aside.
5. In a stand mixer, add 12 large egg whites and cream of tartar. Beat until foamy.
6. Gradually add the 190 g sugar until soft peaks form.
7. Add in vanilla extract and continue beating until stiff peaks form.
8. Transfer the meringue (egg white mixture) to a larger bowl.
9. Sift and carefully add the flour-sugar-salt mixture using the cut and fold technique and using a rubber spatula. Do this in three portions and make sure to scrape down the bottom and sides of the bowl.
10. Now, carefully mix the sprinkles to the mixture.
11. Transfer the mixture to an ungreased tube pan.
12. Bake in the preheated oven at 350 F for 40-50 minutes or until a toothpick inserted in the middle comes out clean.
13. Remove the pan from the oven and invert the pan/turn the pan upside-down so the cake doesn’t deflate or sink too much.
14. Let the cake cool completely (about 3 hours).

For the ganache:

1. In a heatproof bowl, add chopped dark chocolate. Set aside.
2. In a saucepan, add heavy/whipping cream. Heat until you see bubbles around the edges. Pour over chocolate and let sit for 2 minutes.
3. Using a whisk, mix chocolate and cream until glossy.

When the cake has cooled completely:

1. Run a knife around the edges of the cake. Transfer to a serving plate and top with dark chocolate ganache and more sprinkles.