1. Combine chocolate and butter in a bowl and melt over a double boiler.
2. While chocolate is melting, combine sugar, eggs, and egg yolks in a stand mixer with a whisk attachment. Whip egg and sugar mixture till pale in color, and when you lift the whisk out, it briefly holds its shape.
3. Once the chocolate melts, slowly pour it into the egg mixture, having the stand mixer on the lowest setting.
4. Sift the flour and fold it into the batter.
5. Let the batter rest for one hour in the refrigerator.
6. Using 4 oz soufflé molds or ramekins, spray with cooking spray and fill with batter. Fill them almost to the top.
7. Bake at 425 degrees for 8 to 10 minutes. Cakes are done when the top starts to crack, and they still have a little jiggle to them when you give them a shake.
8. Serve warm with a side of whipped cream and berries.

*For gluten-free, can substitute flour with ½ cup rice flour