I am just a hobby baker and decided to make some cake layers to freeze to get a bit ahead for the holidays.  My DH who is such a great guy offered to help weigh out the dry ingredients for Kara's Perfect Chocolate cake recipe.  I printed out the recipe and as I was doing other things in another room.  Suddenly he calls out that there is "too much dry ingredients to fit in the mixer".  Thinking he is nuts since I have a 6 qt KA, I mosey into the kitchen,  He is right.  I look at the recipe I had printed.  Apparently i tripled the recipe on the recipe calculator to see what I would need to make the recipe three times.  I was floored. How could I have done that?  So, we put all the dry ingredients into a huge XL bowl and mixed them up. I now have the dry ingredients for  three recipes.  

I am really math challenged so bear with me.  I have 39 oz of flour, 64 oz of sugar, 9 oz of dutch cocoa powder, 2.25 tsp salt and 7.5 tsp baking powder all nicely mixed together with a whisk.  Since we have a triple recipe I can divide that into three and just store the dry until ready to make the cake.  HOWEVER, just dividing into three may be a problem.  First, I have no way to weigh the total ingredients.  OK, so I think I can just add up the total oz and divide by three and be done, but I am wondering if that is going work.  I added salt and baking powder so would that screw up the weight?  I cannot imagine that the BP and salt would be that much weight.  But I am afraid that it would affect the finished cake.  Ya think that the salt and baking powder weight is going to muck up my math?  I haven't done anything with it yet, it is still in the big 'ol bowl.  

I guess I would laugh but i just don't to make a big mess of this and all the sugar, flour and cocoa in there be goofed up.

Thought I would run this up on the board for some input before I decided what to do...

well, i split the dry ingredients into thirds (weighing) and finished one recipe.  Disaster.  The cake was gummy and raw in the middle after almost an hour in the oven.  Burnt edges and raw middle.   I am stumped and very disappointed.  Not that the flour and sugar was such a waste but all my dutch cocoa was expensive!  Anyone have any suggestions?

Wow, I hope some of the experts here will be able to figure this out. I am not too good at figuring out something such as this magnitude . Even if you divide it up evenly by three what is to say that each division would have the correct amount of sugar,cocoa or baking powder, etc. since they are all mixed together. 

Good luck and hopefully someone here will be able to help you. Sorry I can not be of much help with this.  This sounds like something that I would do!! If anyone could mess it up it would be me!!! Take a deep breath and wait to see what others here have to say!! Try not to freak out!!!

Dump it and start over.  IF the ingredients were all measured correctly, then it sounds like they were not mixed enough and you didn't have enough of one thing and too much of another.  Regardless, this means the ratio for the remainder would also be off - and there's no way to know how to salvage it.

Live and learn.

yep, BrandisBaked, i have come to the same conclusion.  *sigh*  I just have to double and triple check myself before I begin a new recipe.  Totally my fault and like you say...live and learn.  

I've done similar things, mostly on purpose, though.  Once you have a big batch of dry ingredients that must be divided down, you first have to sift them together  a lot of times.  Not just whisk them together.  You have to be certain they are fully and equally incorporated.  That's accomplished by multiple siftings - meaning at least three times, and 5-8 times is way better.  At that point you can, indeed, weigh out (or use dry measures) divisions of the dry ingredients.  

But, basically, too late now.

Hmmm. Burnt edges and raw middle? That part sounds like an oven issue with your temp and/or time.

thanks leah-s...I should have waited before I dumped it, it is possible to that I could have salvaged it...but, I felt the loss of the flour/sugar/cocoa was ok, trying again and adding the butter, egg whites, etc would have cost more in the long run.  with perhaps the same outcome...

MimiFix...new oven, have an additional internal digital thermometer which i monitor closely so I am not sure that was a factor.. 

I agree with Bandisbaked...Dump it and start over! Seems like a high ratio of sugar to flour in recipe

Maybe I'm not fully understanding but Why not get a big mixing bowl and make the triple batch recipe? Sure you'll have to mix by hand but it's better then tossing everything because it won't fix in a mixer. It's cheaper to buy a big bowl if you don't have something big enough to mix in then to toss ingredients.