Western Kentucky Chocolate Sheet Cake

Western Kentucky Chocolate Sheet Cake

I lived in western Kentucky for two years, and became deeply attached to this tender, tasty, cocoa-based cake, with its simple icing that is poured on while the cake is hot. The cake bakes in a 10 X 15 glass baking dish, the same sort one would use for an extra large casserole or a single recipe of Janice Kay's and Judy Rosen's Blonde Brownies.

Otherwise stay with me: I am going to describe the steps to making this cake in some detail, because I want children and first time cooks to add Western Kentucky Chocolate Sheet Cake to your never-fail can-do lists.

Western Kentucky Chocolate Sheet Cake Recipe and Instructions

Turn on your oven to 400 degrees, and put a rack in the middle of the oven. Locate your 10 X 15 baking dish, preferably glass. Slather its sides and bottom thoroughly with a baker's spray like Baker's Joy, or a regular flavorless non-stick spray, or flavorless oil, or butter. Do any of these well and you will be able to extract your cake slices easily after the cake is baked.

Alternate Equipment Tip: You don't have a 10 X 15 glass baking dish? You can also use a 9 X 13 size, much more common. Lower the oven heat to 375 degrees, and plan on an additional 10 minutes or so for the baking time.

In a heavy-bottomed, medium-sized saucepan, place:

1 cup water 1 cup (two sticks) unsalted butter 4 level (more or less) Tablespoons unsweetened cocoa powder (Hershey's original style works fine, as do costlier Dutch-process types; do NOT use any type of powdered hot chocolate drink mix - just plain unsweetened cocoa powder)

Turn the heat on medium low, and stir this mix occasionally with a whisk as the butter melts. The whisk will smooth out the cocoa lumps.

As the cocoa-butter mixture melts and melds, take out a large mixing bowl. Measure these dry ingredients into it:

A tip about measuring flour: Spoon flour from your bag or canister into a measuring cup. Do not dip the measuring cup into the flour. It is soooo tempting, but it results in packing too much flour into the cup, and that results in a drier, tougher cake.

2 cups all purpose or unbleached flour 2 cups white sugar 1 level teaspoon salt

Use a large whisk or wooden spoon to stir the dry ingredients together well. Alternatively, use your clean hands for this mixing.

How is your saucepan of cocoa-butter-water doing? As soon as the butter is melted, turn off the heat, whisk well so the mixture is smooth and dark, and dump the mixture into the bowl with the flour-sugar-salt. Whisk or stir about seven strokes, until the mixture is nearly unified, but not quite. (The less you can stir here, the more tender you cake will be, but don't worry about it, because your cake is going to be tender in any case.)

Into the nearly unified mix, add the following:

1/2 cup buttermilk 2 whole large eggs (just crack them on the counter, and pull the shells apart over the bowl so the whole slick innards fall right in; fish out any piece of shell that fall into the cake, please) 1 teaspoon baking soda 1 Tablespoon vanilla extract

Stir or whisk just until the whole mixture is one smooth color. Pour into your well-greased baking dish, and put the dish on the middle rack.

The cake will likely need to bake for 20 minutes at 400 degrees. You have work to do while it is baking.

Set a timer for 10 minutes. This will signal you when to start making the icing, which will be poured over the hot cake when it comes from the oven. You do not need to wash the saucepan or mixing bowl at this point, because you are going to use each one again to make the icing for the cake.

When your 10 minute timer bell dings, first reset it for five minutes - when you will check the cake for doneness.

Then begin making the icing.

In your heavy-bottomed saucepan, place:

1/2 cup (1 stick) unsalted butter 1/3 cup milk 4 more or less level Tablespoons unsweetened cocoa powder 1/2 teaspoon salt

Turn the heat on low under the saucepan, and stir with your whisk or spoon A LOT. This mixture can stick and burn before you know it. (And if it burns, it is inedible and nasty. Throw it out.)

Your goal is to bring the icing mixture to a full rolling boil, which means bubbles will rise and pop all over the surface of the liquid. Stir the mixture about once every 30 seconds, just a quick stir all around, including the edges of the pan, so nothing gets stuck and starts to burn.

Alternate instruction: You can turn the heat up to medium on the icing mixture IF you can stir the mixture constantly, without leaving it to answer the door, kiss your sweetheart, or let the dog out. Do not turn up the heat to medium unless you will be with the saucepan all the way to boiling.

Into your large mixing bowl, place:

1 pound  confectioner's sugar (same as powdered sugar) (1 box equals one pound, and measures 3 1/2 cups unsifted)

As soon as your butter-cocoa-milk mixture boils and you have smoothed it out with your whisk or spoon, pour it carefully over the confectioner's sugar in your mixing bowl.


2 teaspoons vanilla extract

Whisk or stir thoroughly, until very smooth. The icing texture at this point will be semi-solid -- a little runny, a little thick.

Set your bowl in a warm place and check on your cake.

Has the five minute timer dinged? That means the cake has baked for 15 minutes. Although the cake typically requires 20 minutes at 400 degrees to bake completely, ovens vary, and other factors (humidity, flour, butter, egg size) can influence how quickly the cake bakes. Some cakes finish early at such a high oven heat. It is a good idea to check early.

Add your 10 minute and 5 minute timers together and your cake will have baked 15 minutes at 400 degrees when the second timer dings. Time to check the cake. Your options:

  • If you can see through your oven door and the cake still looks a bit depressed in the middle, and has not started pulling away from the sides of the baking dish, leave it in the oven another five minutes.
  • If you cannot see through your oven door, open the door as quickly and as narrowly as you can, and take a peek. Look for the depressed middle - a sign that your cake is still baking, and needs the remaining five minutes -- very, very likely.


  • If the cake is smooth across its middle and appears "set" in the very middle, go ahead and open the door. Follow the instructions below for testing the cake for doneness.

After 20 minutes, open the door and use potholders to grab the rack and pull it toward you, moving as quickly as you safely can.

  • If you see the middle of the cake jiggle as it comes toward you, it needs more baking. Shut the door and continue baking for another three minutes before testing again.
  • If the cake does not jiggle, touch the very middle of it with your fingers. It will not burn you if you use a quick, light touch.
  • A cake that is not done will feel a bit squishy, almost like a water bed.
  • A cake that IS done will feel very soft, but still firmed up under your touch.
  • Your fingers may leave a tiny dent, but they will not sink through the top of a cake that is done.
  • In addition, sometimes the cake will begin pulling slightly away from the edges of its pan when it is done all the way through.

More than likely, your cake is done after 20 minutes. And - don't tell anyone this secret - the worst that will happen if you take it out too early is that it will fall and be a bit more dense and moist in the middle. If this happens -- don't tell anyone this, either -- most people will like those slices best. They will be super-moist, almost like a tunnel-of-fudge cake, once you pour on the icing. Err on the side of under-done rather than overcooking the cake. Baking it too long makes it dry and can even edge toward that dreaded burned chocolate taste. So if in doubt - take it out.

So! Your cake is done and your icing is done. It's time to introduce them.

Pour the warm icing over the hot cake. Move the bowl as you pour, so you help the icing spread. Use a scraping spatula to get all the icing from the bowl onto the cake. The icing will become thinner when it has been on the hot cake for a moment. If there are bare spots on the cake top, very gently use the spatula to pull a bit of warm icing from a thicker pool over onto the bare spots.  It will be easy to move icing to cover the whole cake if you drag from the thicker spots very gently. If you rush or use a heavy touch, you can tear the cake underneath. If that happens - Dang! You'll have to eat the torn up spot, or find a waiting hungry mouth to feed.

This cake, unlike most others, can be eaten immediately, even while it is warm. If you let it cool completely, the icing will become slightly set, and the cake will be a bit less messy to serve and eat. Enjoy Western Kentucky Sheet Cake!

Ways to change the basic flavors and textures of this cake, if you wish:

  • Add 1 tsp ground cinnamon to the flour/sugar mixture.
  • Replace the 1 cup water (for the cake) with 1 cup strong coffee.
  • Replace 1/3 cup milk (for the icing) with 1/3 cup espresso or strong coffee.
  • Add 1/2 cup finely chopped nuts to the cake or the icing, or both. Black walnuts, toasted pecans, toasted English walnuts, or cashews are delicious. In most forms, almonds are a bit too crunchy to be enjoyable in this unusually tender delicacy.
  • Substitute bourbon, rum, amaretto, or a berry liqueur (Cassis, Chambord, Kirschwasser, Framboise) for the vanilla in the icing.

Just the Recipe: Western Kentucky Sheet Cake (for Experienced Cooks)

Preheat oven to 400 degrees F. Prepare a 10 X 15 baking pan.

Cook until melted, stirring often until smooth:

1 cup water 1 cup unsalted butter 4 Tablespoons unsweetened cocoa, regular or Dutch process

Mix together in a large mixing bowl:

2 cups all purpose or unbleached flour 2 cups white sugar 1 level teaspoon salt

Add melted butter-cocoa mixture and stir until nearly smooth.


1/2 cup buttermilk 2 eggs 1 teaspoon baking soda 1 Tablespoon vanilla extract

Stir just until barely blended. Turn into prepared pan.

Bake 20 minutes.

While baking, prepare icing.

Mix and bring to a boil:

1/2 unsalted butter 1/3 cup milk 4 Tablespoons unsweetened cocoa, regular or Dutch process 1/2 teaspoon salt

Place in a large mixing bowl:

1 pound confectioner's sugar

Add boiling cocoa-milk-butter mixture. Stir until mixed.


2 teaspoons vanilla extract

Stir until smooth. Pour over hot cake.

I offer this recipe and description as a grateful toast to the beloved memory of a western Kentucky mentor, friend, and life guide who has moved on to much better barbeque and chocolate cakes, no doubt, in the next world.