Rhubarb Skillet Cake with Jaggery Crumb

The night before you plan to bake, beat the spelt with yogurt until loosely combined. Cover the bowl with tight-fitting plastic wrap lest it dry out, and set it in a warm spot in your kitchen overnight for 8 to 12 hours.The next day, chop the rhubarb into 1/4-inch dice. Toss it into a bowl and sprinkle 1/2 cup jaggery over the rhubarb. Allow the rhubarb to macerate in the jaggery for about an hour.Preheat the oven to 350 F.Melt 3 tablespoons of clarified butter or ghee over low heat in a well-seasoned 9-inch cast iron skillet. Toss the macerated rhubarb into the hot butter and saute about 2 minutes. Turn off the heat and prepare the cake batter.In a large mixing bowl, beat the eggs with 3/4 cup jaggery until smooth, then beat in the vanilla extract. Working 1/2 cup at a time, beat in the batter of yogurt-soaked spelt flour. In a separate bowl, whisk high-extraction flour with 1 teaspoon ground cinnamon, orange zest, baking soda and salt. Working 1/2 cup at a time, beat the dry ingredients into the wet ingredients until they form a smooth batter.Prepare the jaggery crumb in a small to medium-sized mixing bowl. Beat the almond flour and jaggery together with cinnamon, then slowly beat in 3 tablespoons melted butter.To assemble the cake, pour the cake batter into the skillet over the rhubarb.

Sprinkle the jaggery crumb over the cake batter, and bake until a toothpick inserted into the cake's center comes out clean - about 1 hour. Allow to cool about 20 minutes before dipping into it with a spoon and scooping it out onto waiting plates.