Saunders called their cake Chocolate Buttercream Devil's Food Layer Cake but over the years people just started calling it Bumpy Cake. The cake has rows of buttercream across the top that are then covered in a chocolate glaze.
Years ago, I think I was 10 or 12, my family got their hands on the recipe. I remember my mom trying to make it once. She did not succeed. The next attempt was made by my sister and I. It turned out a little better. Over the years, I have made this cake many times. I have figured out a few details that were not in the original recipe.
When my sister or brother plan a trip to Michigan, they call ahead and make sure I have at least 3 days notice. That way they are guaranteed a cake. I can make the cake in 2 days if I get an early enough start. You should know that this does require enough time to freeze the cake--I usually leave it in the freezer over night.
Step 1: Critical (and Weird) Special Ingredient
The ingredient is sour milk. Yes, I know. Normal people pour this stuff down the drain. My family uses it as an excuse to celebrate. My baby brother used to manufacture the stuff.
My brother would wait until there was only about a cup left in the milk jug. He would then rearrange all the things in the bottom of the refrigerator so that he could hide the milk in the back, behind enough things that nobody knew it was there. He even got really good at arranging things so that it did not look like there was anything hidden.
After a few weeks, he would 'discover' the spoiled milk. Since it was a terrible crime to 'waste good food', he would call me and request that I stop by and pick it up.
My own children do not have the self control to allow milk to spoil naturally so I usually have to artificially manufacture it. Measure out a cup of milk. Add a tablespoon of lemon juice or vinegar. Stir and wait 15 or 20 minutes. Instant (or almost instant) sour milk. The chunkier, the better. I know--this sounds gross to most people.
Trust me. It may only be a cup but it makes all the difference at the end. Don't use fresh milk.
Step 2: Ingredients:
3/4 cup shortening
2 cups sugar
1 cup sour milk
1 teaspoon vanilla
2 1/2 cup cake flour--sifted
2 teaspoons baking soda
1 teaspoon salt
1/2 cup cocoa
1 cup boiling water
1 cup shortening (or butter)
3 cups powdered sugar
1/4 cup evaporated milk
1 teaspoon vanilla
1 tablespoon butter
2 squares unsweetened chocolate
1/2 cup evaporated milk
4 cups powdered sugar
I always use Hershey cocoa. I made the mistake of using Nestle brand once. (The store was out of Hershey.) My sister could tell the difference. I was reminded of my mistake many times in the following years. You may be able to get away with an inferior brand but I can't.
The original recipe called for making the buttercream out of granular sugar. I did not care for the granular texture. If you make the buttercream a few days ahead of time, it is not too bad. I still prefer to use the finely ground sugar.
Step 3: Preparing the Pan(s)
Grease and flour the pan(s) that you will be using.
Step 4: Making the Cake
Sift together all the dry ingredients--including the flour, baking soda, salt, and cocoa. I tried skipping the sifting once--too lazy to locate the softer. It make a big difference in the texture of the cake. It is worth the effort. You can sift the dry ingredients several time if you have a lot of excess energy or a couple of older kids who like to help. Younger kids will probably make too big of a mess.
I usually add the vanilla to my milk--so I don't forget it entirely.
Alternately add some of the flour mixture and the milk to the cake until both are incorporated. If you add all the flour at once, it will fly everywhere. If you add all the milk at once, the mixture gets to thin and it is challenging to mix the flour in without huge lumps.
Add the boiling water and beat it slowly at first. Once the risk of splashing hot liquid is gone, switch to a higher speed and beat for 2 minutes.
Pour into the prepared pan(s). Bake at 350 degrees for 22 minutes if you are using round pans. It will take a bit longer for a sheet cake. Check for done-ness by poking it with a toothpick. It will come out without any batter stuck to it if the cake is done.
Flip round pans onto cooling racks. A sheet cake is easier if you leave it in the pan.
Step 5: Prepare the Buttercream
Beat the sugar, shortening/butter, milk, and vanilla. If it is too sweet, add just a tiny, tiny, tiny pinch of salt. Beat until it is fluffy. You may need to add a bit more milk or sugar--depending on the humidity.
I did this step late at night. Getting the cake together before I fell asleep was more important than taking pictures.
Step 6: Frosting the Cake--the First Time
At this point, I want to make sure that the chocolate layer will go on nicely, so I frost the entire curved side of the cake with a thin layer of buttercream. I make sure to fill in any gaps between the layers. (My husband said this step reminded him of spackling a wall.)
On the top of the cake, I start with a thin layer of buttercream. Then I draw 4 lines across the cake. These lines make it easier to equally space the ridges on the top of the cake.
I used to put the buttercream in a pastry bag and pipe a large stripe across the line. I don't bother any more. Now I just sculpt the buttercream with a butter knife. I am reasonably quick now that I have had years of practice.
Once you are satisfied with the shape of everything, put the whole cake in the freezer. Leave it there until it is frozen solid. It will thaw quickly so you should leave it in the freezer while you make the chocolate glaze.
Step 7: Prepare the Chocolate Glaze
In a small pot on the stove, melt the butter and chocolate. Keep the temperature as low as possible so you don't burn the chocolate and stir constantly. Add a small amount of evaporated milk. Sift in some of the confectioners sugar. You want it to become a thick paste. Add just a little milk. Now it should be a thinner paste. Alternate between sugar and milk keeping the mixture on the thick side. The difference between the last two pictures is about a tablespoon of milk.
This is the hardest part of the whole cake making process. If you add all the milk at once, the glaze will get clumpy when you add the sugar. If you start with all the sugar, you will have a powdery mess that is hard to get to come together. If you don't sift the sugar, your glaze will have sugar lumps that are still white if you smash them open. If you make the glaze too thick, it will be a frosting instead of a glaze. If you make it too thin it will drip off the cake. Keep in mind, that it will still taste good, even if your first attempt or two doesn't look perfect.
Once you have all the sugar incorporated, you should have a thick but pour-able consistency. Taste it. It should be sweet but not too sweet. The buttercream will sweeten the overall cake.
Once you are satisfied with the taste, you need to thin it down so that it is a glaze and not a frosting. When you pour it from a spoon, it should leave a thin coating on the spoon. If you let the spoon cool for a minute, it should be too thick to pour easily. Be careful not to thin it too much--trying to thicken it again usually leaves you with a lumpy glaze.
Keep the glaze on the stove. Have someone stir it for you if you have to go all the way to the basement freezer to get the cake.
Step 8: Frosting the Cake--the Second Time
Once the top is done, move on to the side of your cake. Work on a small patch at a time. I almost pat the glaze in place rather than spread it. Every now and then, give the glaze in your pan on the stove a quick stir. This will keep to more evenly warm.
Step 9: Eating the Cake
My father got upset if people cut this cake 'incorrectly'. (There was also only one way to properly load a dishwasher. But the difference is, we still observe the slicing the cake rules.) Refer to the drawing to see the approved slicing pattern. This allows the buttercream to retain its unique and distinctive design. The first and last slice on each half do have more frosting than the rest of the slices.
My father loved sweets but when it came to this cake, even he had to limit the size of his piece. This cake is very rich. Keep that in mind when slicing it.
My brother figured out that when frozen, you could eat larger pieces. He took to snatching up any left over cake. He sliced it into individual portions and packed it away in the basement freezer--being careful not to make it easy to find. He would then have it with a scoop of vanilla ice cream.
If you are not freezing the cake, it should be stored in the refrigerator during the summer heat. (The top layer actually slid off the cake on one particularly warm day.) Any other time of the year, it can be stored on the table with a cover over it.
Step 10: Leftover Glaze
He kept it in the refrigerator until he was going to use it. He would warm it just enough to liquidity it. Then he poured in on his ice cream. He insisted that it was the best hot fudge sauce because it stayed on the ice cream instead of just pooling under it in the dish.
My son used to take a bowl of the glaze and a butter knife. He would sit on the kitchen floor and frost the back of a teddy graham cracker. Then he would add another teddy graham. He called them "bearwiches". He always tried to get a whole plate full so that he could go around and serve people. It was very hard since he ate as many as went on the plate. It was adorable.
My son is 18 now and I didn't think that he would pose for a picture--so I didn't even ask. I should have taken the picture 16 years ago.