Posted on 08 May 2011 at 19:33h

This weekend is confirmation weekend in Norway which means hoist the flag and eat lots of cake. The daughter of one of our neighbours was getting confirmed so Hilary decided to bake a cake. The recipe was for a normal sized cake but confirmation Sunday calls for a super size cake so Hilary went for double quantities. The cake was a carrot cake by the way. You'd think that double quantities would mean double baking time but after double the half hour for a normal sized cake the cake was far from ready, now carrot cake is supposed to be moist but this was dripping wet. After an hour and a half it was finally cooked as you can see in the photo.

I was wondering how you calculate the effect of increasing quantities. Here is a rule of thumb I got from a google search:

• Remove 1/3 of the cooking time.
• Double the remaining amount.
• Add your original third back on.
  Why not multiply by 5/3?

That would give 50 minutes which wasn't nearly enough.
It's probably got something to do with the shape of the cake as well.
Doubling the ingredients doesn't double the distance to the centre so why does it take so long to cook? maybe its something to do with the carrots?