Yes, that is correct, I made a beet cake and it was delicious! Apparently the original red velvet cakes utilized beet puree to lend moisture and tint back in the dye before being unceremoniously replaced with red food coloring.
I don't even remember how I found this recipe but once I hit on the idea, I perused several variations. That got me all confused because some called for as few as 2 eggs and other s as many as five with all other proportions being relatively the same. I only had three eggs so I decided to go with it. Nigel Slater's recipe, which I came upon first, was adorned with creme fraiche and poppy seeds but I decided to up the ante and fill it with something, plus sub creme fraiche for mascarpone because, well, I love it.
I also found Slater's directions a bit fussy so if you'r the type that likes super-detailed instructions, see his version. If you find the overwhelming like I do, see my simplified version below. Note: I didn't measure my beets in ounces. I boiled three beets, peeled them and pureed them and used a scant cup for the cake, which left me with a scanter cup for another use. Honestly, next time I'd probably use canned beets, which I never would normally eat but in this preparation, I don't think anyone would notice. Plus, you save yourself some time and pink hands.
8 ounces fresh beets
7 ounces fine dark chocolate (70%)
1/4 cup hot espresso
3/4 cup + 2 tablespoons butter
1 cup + 2 tablespoons all-purpose flour
1 1/4 teaspoons baking powder
3 tablespoons good quality cocoa powder
1. Lightly butter an 8-inch springform cake pan and line the base with a round of baking parchment. Heat the oven to 350 degrees F.
2. Cook the beets, whole and unpeeled, in boiling unsalted water. Depending on their size, they will be tender within 30 to 40 minutes. Young ones may take slightly less. Drain them, let them cool under running water, then peel them, slice off their stem and root, and process in a blender or food processor until a coarse purée.
3. Melt the chocolate and espresso (or strong leftover coffee!) broken into small pieces, in a small bowl set over a pot of simmering water. Cut the butter into small pieces -- the smaller the better -- and add to the melted chocolate. Let melt over very low heat.
4. Sift together the flour, baking powder and cocoa. Separate the eggs, putting the whites in a large mixing bowl. Stir the yolks together.
5. Remove the bowl of chocolate from the heat and stir until the butter has melted into the chocolate. Let sit for a few minutes, then stir in the egg yolks.
6. Fold in the beets.
7. Whisk the egg whites until stiff, then fold in the sugar. Fold the beaten egg whites and sugar into the chocolate mixture.
8. Lastly, fold in the flour and cocoa. Transfer to the prepared cake pan and put in the oven, decreasing the heat immediately to 325 degrees F. Bake for 40 minutes. Do NOT OVERBAKE! The rim of the cake will feel spongy, the inner part should still wobble a little when gently shaken. Test with a cake tester or toothpick too -- if it is still gooey in the center, continue baking just until moist crumbs cling to the tester. Set the cake aside to cool (it will sink a tad in the center), loosening it around the edges with a thin icing spatula after half an hour or so. It is not a good idea to remove the cake from its pan until it is completely cold.
This is where Nigel's recipe ends and mine takes over. I let the cake cool overnight and when I tried to remove it from the pan (which I neglected to line with parchment), it stuck to the bottom. Luckily, my amazing husband taught me a trick to heat the underside of the cake pan with a creme brulee torch and then, voila, it popped out beautifully! Using a long, serrated knife, cut the cake horizontally into to equally-sized rounds. I used a small 4 ounce jar of raspberry curd I made some months back (and kick myself for not noting how I made it!) and spread that on the bottom layer and then topped it with the other layer. I wouldn't skip this, it was a very thin layer but it seeped into the whole cake and permeated it with tart, fruity, elegant moistness. Then I iced the whole thing with mascarpone frosting, see recipe below.
4 ounces cream cheese, softened
4 ounces mascarpone
1 stick butter, softened
1 cup powdered sugar
1 t. vanilla