One of our friends had a tapas party for her birthday this weekend, and I couldn't think of a tapas recipe that would travel well, so I decided to make a flan.
But not just any flan. (Insert "Mission Impossible" music here.) Flan Imposible.
Flan Imposible, or Chocoflan, is really two desserts in one: velvety vanilla custard over a layer of gooey chocolate cake. It gets its name from the magical process by which the custard and cake layers switch positions during baking. With not too much work, you get two desserts and entertainment!
The recipe I used is Fany Gerson's, reprinted in Saveur, though this is a classic Mexican dessert, so many versions of the recipe abound, including ones that use cake mix (if you want Chocoflan in a hurry). The centerpiece for this flan is cajeta, which is a goat's milk version of dulce de leche. Unfortunately, even though we live mere blocks from the so-called Latin Quarter of Boston, I could not find cajeta anywhere. So I used dulce de leche instead. Really, though, you could just use a store-bought caramel sauce. It'll still be good. In fact, next time I might just make a quick caramel sauce at home; I think a less sweet, more bitter, almost burnt caramel would go really well with the sweetness of the flan and cake.
Preheat the oven to 375°F. Lightly grease the bottom and sides of an 8-inch cake pan, or you can use a bundt pan, which I think is prettier.
Pour 1/2 to 1 cup of the cajeta (or whatever kind of caramel sauce you're using) over the bottom and sides of the cake pan using a brush or the back of a spoon (you can heat the sauce very slightly in the microwave so that it is easier to spread). If you love caramel, you should go all out and use a full cup of it. But the dessert is plenty sweet already, so I used just enough to coat the pan.
Then make the cake layer. Combine 3/4 cup sugar, 3/4 cup flour, 1/3 cup unsweetened cocoa powder, 1/2 teaspoon baking soda, 1/4 teaspoon baking powder, and a pinch of salt in a large bowl and whisk until well blended. In a separate bowl, whisk together 1/2 cup buttermilk, 3 tablespoons vegetable oil, 1 egg (at room temperature), and 1/2 teaspoon vanilla. Add to the flour mixture, whisking until thoroughly combined. Pour the cake batter into the pan and set aside.
Then make the flan layer. Combine 12 ounces evaporated milk, 14 ounces condensed milk, 4 eggs, 1/2 teaspoon vanilla, and 1/2 teaspoon salt in a blender and blend until there are no visible lumps. Pour gently over the cake batter.
Cover loosely with foil, place in a large baking dish, and fill the baking dish with hot water so that it comes halfway up the sides. Bake until a toothpick inserted into the center comes out clean, about 50 minutes. (I forgot to cover with foil, so there was a thin layer of flan that remained at the top. Grr.)
Remove the cake pan from the baking dish and allow to cool for at least 4 hours or refrigerate overnight. To unmold, lightly pass a warm knife around the edge, place a plate or dish on top, and carefully but rapidly flip over. Garnish with toasted nuts or fruit. Serve cold or at room temperature.