I am baking Shirely Corriher’s carrot cake for my friend’s birthday next week. (http://books.google.com/books?id=b-iwjIb2RxwC&pg=PA72&lpg=PA72&dq=carrot+cake+shirely+corriher&source=bl&ots=uw6P5q0wye&sig=lN-jms-gW5ruzV_gs4w12OWdZxA&hl=en&ei=HkQ1TeLjM4bCsAOmytH_BQ&sa=X&oi=book_result&ct=result&resnum=2&ved=0CBwQ6AEwAQ#v=onepage&q&f;=false)
The recipe (for two cakes) calls for two 8x2 pans, but I am planning to do only one cake in a 9x2 pan. The 9x2 pan is 1.24 times bigger than the 8x2, and since I am halving the recipe, my scaling factor would be 0.62. I also don’t have self-rising flour, so I plan to use a mixture of all purpose and baking powder + salt.
My concern is how I scale the baking powder. The original recipe uses 2 1/3 c. self rising, which would be equivalent to approximately 2 1/3 c. all purpose, 3.5 tsp baking powder, and 0.6 tsp salt. Do I just scale the baking powder with the 0.62 factor, or is it handled differently?
My calculations for one 9x2 pan are as follows (with rounding). Does this look right?
1.25 c. nuts
1.25 Tb butter
0.5 tsp salt
1.5 c all purpose + 2.25 tsp baking powder + 0.4 tsp salt
cinnamon, nutmeg, orange zest
2 large eggs
1 egg yolk + 1 tsp.
1.25 c light brown sugar (I only have dark brown…so…. 1/2 c. white + 3/4 c. mixture of dark brown sugar containing 2 Tb white sugar)
1/2 c. + 2 Tb canola oil
3/4 tsp vanilla
2.5 Tb orange juice
2 c. finely grated carrots
Also, I will not be baking the cake at my house. Will it be ok to pre-mix the dry ingredients in a ziplock bag for a couple of days? I am concerned that the leavening might lose its activity.
Thank you for the help!