Preheat the oven to 325°F.
Lightly butter a 2-quart oval baking dish and set aside.
On the stovetop or in the microwave, melt the 2 sticks of butter and set aside to cool.
In the bowl of a stand mixer fitted with the paddle attachment, beat the eggs and sugar on medium-high speed for 5 to 10 minutes, until very thick and light yellow.
Meanwhile, sift together the cocoa powder and flour.
Once the egg and sugar mixture is ready, add the vanilla bean seeds, framboise (if using), and the sifted cocoa powder and flour mixture. Mix only until combined.
With mixer running on low speed, slowly pour in the melted and cooled butter into the mixer. Mix until just combined.
Pour the batter into the prepared oval baking dish and place it in a larger roasting pan with high sides.
Add enough very hot tap water to the pan to come halfway up the side of the dish.
Then bake for 60 minutes, but no longer.
The edges will be set, but the center will appear quite underbaked.
