Separate the egg yolks.
Whisk the yolks well.
Melt the chocolate either over a double boiler or in the microwave.
Mix the melted chocolate and yolks thoroughly.
Add sugar and mix evenly.
Add flour to make a dough.
Grease the pan with oil.
Pour the batter into the pan and cook on medium-low heat.
Flip it over and finish cooking.