250gs of Culinary Chocolate. (Tip: try looking for a kind of chocolate that isn't too sour or too sweet.)
If you want to make it bigger just keep a ratio of 50gs of chocolate per egg.
First off, you wanna separate the egg yolk from the egg white. Whisk them separately.
Second, melt up your chocolate.
After whisking both the egg yolk and the egg white, pour both and the chocolate all together. Whisk them and make sure they are all mixed pretty well. The chocolate has the tendency of being heavy therefore falling to the bottom of the bowl.
Next up, heat up your oven up to 180 Celsius. Meanwhile get your cake pan and butter it up.
Throw in the mix in the cake pan, 30 mins on the oven and there you go.
The cake might look a bit hard or humid but it's normal. It's got high density on chocolate and eggs since it doesn't use flour or baking powder. You can try mixing and matching chocolate types from dark chocolate to white chocolate and so on so forth. It's a pretty basic but tasty cake recipe.