Preheat oven to 350°F. Butter a 9-inch springform pan sprinkle with sugar. Tap out the excess.

Add the chocolate, oil, and butter to the top of a double boiler or large heatproof bowl set over a saucepan of simmering water. Stir it often until completely melted. Remove the bowl and let it cool off until it's barely warm.

Crack and separate 4 of the eggs - put the whites in the bowl of a stand mixer or in a large mixing bowl and put the yolks in a separate large mixing bowl

To the yolks add the cocoa powder, vanilla, salt, ¼ cup of the sugar and the remaining 2 eggs. Whisk until smooth and combined.

Whisk a few tablespoons of the chocolate into the yolk mixture then slowly add the yolk mixture to the chocolate whisking well.

Beat the egg whites on medium speed until frothy then gradually beat in ½ cup sugar until firm peaks form.

Fold half the egg whites into the chocolate mixture until completely combined then repeat with the remaining half.

Pour the batter into the prepared pan and evenly smooth out the top. Sprinkle with the remaining 2 tablespoons sugar (I forgot this step!).

Bake 40 - 45 minutes until tall and puffy, the edges should be pulling away from the pan.

Cool completely on a wire rack. The cake will collapse on itself and crack as it cools.

Beat the heavy cream and sugar together on medium-high speed until thick and stiff. Remove the side ring from the cake and pile the whipped cream on it. Cut into wedges to serve.

*The cake is great at room temperature but even better chilled. Also good a little warm (or cold) with ice cream or made into a sundae.