I'm not sure whether or not the fine people of Smith Island, Maryland would care for my vegan version of the Maryland Official State Cake, so I have decided to call mine "Columbia Cake", while acknowledging the Smith Island pedigree of this lovely dessert.
I followed the basic guidelines set forth here, and also perused several random internet articles to check out all the possible variations. There are many, but I finally decided to try one of the recipes that seemed the most popular: yellow cake, cooked chocolate frosting, and crushed peanut butter cups between the layers.
I should also mention that I've never actually had the omnivore version of Smith Island Cake, so I was a little nervous about attempting a veganization. This cake was intended to debut at the IC's top-secret surprise birthday party. I consoled myself with the thought that if it was awful, there would be many other desserts to choose from. I thought it was pretty good, though, and I've received enough requests for the recipe that I suppose it went over just fine.
NOTE: You must have vegan peanut butter cups in the freezer overnight for the best results. You will need as many 8-inch round pans as you can rustle up. I bought some E-Z foil pans and did all six layers at once, but you can also just keep swapping out two pans until all your layers are done. But E-Z foil is...E-Zier.
WARNING: my recipe produced only SIX layers, which falls short of the standard 8-12 layers achieved by Smith Island Cake champions. I think you could modify this recipe to make more cake layers: increase everything by half. So, 3 cups soymilk, 3 teaspoons apple cider vinegar, 3 3/4 cups flour, etc.
So...here's the recipe:
For the Cake:
2 cups soymilk
2 teaspoon apple cider vinegar
2 1/2 cups all-purpose flour
4 tablespoons cornstarch
1/2 teaspoon baking powder
1 teaspoon baking soda
1/2 teaspoon salt
1 cup softened non-hydrogenated margarine, like Earth Balance
1 1/2 cups granulated sugar
4 teaspoons vanilla extract
pinch of turmeric
1. Preheat oven to 350 degrees.
2. Set up all your 8-inch round pans. Spray or oil them lightly.
3. Put the vinegar in the soy milk and let it curdle.
4. Mix the dry ingredients in one bowl, the wet ingredients in another, then combine the lot of them in one big bowl.
5. Pour a thin layer of batter into each pan and bake for about ten minutes. This should be sufficient to bake it all the way through. The layers will be so thin that you ought to be able to tell if they're underdone.
6. Cool all the layers completely.
Part 2: the Candy Filling!
One popular version of the Smith Island Cake includes crushed peanut butter cups between the layers. I tracked down some vegan peanut butter cups at my local natural market. You can also find them online at a few specialty stores. You freeze them overnight, then pulse them, still frozen, in a food processor until they are almost completely pulverized.
Part 3: the Frosting!
You'll need: 1 bag of vegan chocolate chips, a large spoonful of coconut oil, 3 tablespoons of soy creamer.
Melt the chips and coconut oil together using your preferred method: microwave, pot on the stove, double boiler, whatever. You'll need to keep an eye on them as they melt so they don't burn. Stir them until the chocolate is silky smooth and shiny. Add the soy creamer and whisk until everything is blended completely.
Part 4: Assembly
Pop out one layer directly onto your cake plate (the layers are very delicate, so you want to move them as little as possible). Sprinkle generously with pulverized peanut butter cups. Add your next layer. Add more peanut butter cups, or you might alternate frosting and candy. Once you've topped off the whole thing with the final layer, pour frosting over the whole thing.
I let my frosting cool slightly as I constructed the layers of cake and candy, and poured it on warm. I used a spatula to get complete all-around cake coverage. It wasn't totally perfect; my layers didn't come out totally even, and it looked a bit like a giant stack of pancakes, but once the frosting cooled it really helped to disguise my mistakes and hold the whole thing together.