This is an amazing recipe, but I have one critique. When I made this for the first time, the batter was slightly warm due to the chocolate and butter mixture still being warm. When this happened, I only had to cook it for 8 minutes. The second time I made this, the cakes were at room temp before cooking, and they only needed 10-11 min. Moral of the story is to try it at 8 min and add more time as to not burn it by having it there for 15 min.
Can the batter be made a day ahead and baked just before serving?