Take 5 ramekin dishes (small white porcelain shallow bowls ideal for baking small cakes) buttered and sprinkle with cocoa.
Melt the butter and chocolate with the ben Marie method (A method of cooking in which food is cooked in a warm water bath). The food is placed in a pan that is then placed in another pan containing warm covering the 1/3 of the bowl, simmering water. It’s an ideal method for melding the chocolate. 
In a mixer bowl add the eggs, egg yolks, salt, vanilla and sugar and beat in the mixer for 5’ Stop the mixer and add in portion the melted chocolate in the mixer bowl and with the spatula and circular motions. Then you have to  sift  ½ quantity of flour and add it to the mixture. Then you sift the rest of the flour on top.
Split the mixture in the 5 ramekin dishes and bake in a preheated oven 200°C for 10’
Let them cool for 2-3 and with a knife with pointed tip cuts smoothly and cleanly around the edge of a ring or pan to remove it easily. Serve it with the whipped cream on top and fresh strawberries