Texas Sheet Cake

Growing up in a family of eight, the first thing that I learned to do in the kitchen was help with the dishes.  We didn't have a dishwasher until I was in my late teens (my father always claimed that we had six dishwashers), so I learned at a very young age how to tackle mounds of pots and pans, plates and cups, glass and silverware.

The next thing that I learned how to do was bake.  Baking has always been a joy to me since then.  Until... now.  Well, three and a half years ago.  What changed?  Our elevation.  We moved from sea level to nearly 5000 feet above, and as anyone knows who has half-glanced at the back of a box of cake mix, there are special directions for high altitude baking.  I've lived at a high altitude before, but never quite so high.  At about 2500 feet, an extra tablespoon or two of flour is about all that it takes to right the ship and keep your cakes and quick breads from falling in.  At 5000 feet, it gets a little more complicated. 

Complicated enough to make a saint swear.  Some of the tricks in the high altitude arsenal are:  more flour, more eggs, less sugar and butter, increasing acidity (adding lemon juice or buttermilk), using a lower temperature and longer cooking time, reducing the leavening, and lowering the rack in the oven down to the bottom.  (A great primer, for those of you interested, would be Susan G. Purdy's excellent book Pie in the Sky: Successful Baking at High Altitudes.) Adjusting my recipes has been such a pain that I've greatly reduced my baking to mostly yeast breads (which just get fluffier, for the most part) and pies, which are not as impacted by thinner air.

When we had our blizzard this week, however, I really wanted to make something chocolate besides the one brownie recipe that still seems to work.  Texas sheet cake seemed like a good choice.  It already has buttermilk in it, so I was hoping that adjustments would be few.  Three rounds of baking later, I managed to come up with a high altitude recipe that works.  (And yes, as usual, my family did not complain about having to consume my failures.   "Hmmm... slightly gooey and fallen-in chocolate cake?  Twist my arm!") 

I love Texas sheet cake.  It's incredibly moist, with a warm hint of cinnamon, and it has the most fudgey, nutty topping.  My husband likes it because it is similar to German chocolate cake, only without the coconut, which he dislikes.  My children like it because it's easy to make and delicious to eat--especially when it is still so warm that the gooey topping runs down the sides of your slice, as in the above picture.  It's the perfect antidote to the blizzard blues.

So without further ado:

Texas Sheet Cake -- Yield:  One jelly roll pan (or one 9x13" pan) of cake.  About 16-24 pieces.
(For High Altitude:  add 2 T. extra flour and 1 extra egg to the cake batter.)

Cake
2 cups sugar
2 cups flour
2 sticks margarine or butter
1/3 cup cocoa
1 cup water
2 eggs
1/2 cup buttermilk (or add 1 tsp. lemon juice to regular milk in a 1/2 cup measure and let sit)
1 tsp baking soda
1 tsp cinnamon
1 tsp vanilla

Icing
1 stick margarine or butter
1/3 cup cocoa
6 Tbsp. milk
1 tsp vanilla
1 tsp cinnamon
1 cup chopped pecans (or walnuts work, too)
1 lb. (4 cups) powdered sugar

Preheat the oven to 400F (or 375F if you have dark coated pans).  Grease a jelly roll pan (or a 9x13, alternately).  Sift the flour and sugar together in a large bowl.  Melt the margarine on medium heat in a large saucepan.  Add the cocoa and water and bring just to a boil.  Pour the hot chocolate mixture into the bowl with the flour and sugar and whisk until thoroughly combined.  Add remaining ingredients and whisk again until combined.  Pour batter into your pan and bake for 20 minutes (or 30 minutes for a 9x13).  Remove the cake from the oven.

During the last five minutes of baking, bring the margarine, cocoa, and milk to a boil in a large saucepan.  (I use the previously used pan.)  Add remaining ingredients and whisk until thoroughly combined.  Beat well and pour over the still warm cake, spreading evenly.  Allow to sit for at least 10 minutes before serving.