Beat egg and sugar until foamy in a bowl. Set it aside.

Melt the chocolate and butter in microwave or on the stove.

Whisk in the chocolate mixture into the egg mixture along with the flour.

Grease the bowl/cup/muffin tin.

Pour the batter into it.

Bake it in microwave for 55 seconds (high heat). Steam it for 8-10 minutes (low medium heat) until the top and side of cake is firm. Bake it in oven at 170 C for 10 minutes.

Remove it out from the mould and enjoy the warm cake. Serve it with powdered sugar, sliced fruit.