This is not the exact recipe for Heidi Swanson's buttermilk cake, although it's pretty close. Heidi uses plums and turbinado sugar on her cake, while I am using huckleberries (blueberries would be fine, too), mixing them into the batter, and then topping the cake with maple sugar. This cake is super moist, delicately sweet and it keeps for several days. It's a little like a giant blueberry muffin.
3/4cuphuckleberries or blueberries,fresh or frozen
3tablespoonsmaple sugaror turbinado sugar
Preheat the oven to 400 degrees and make sure you have a rack near the top of the oven. Heat rises, remember? Butter and flour an 11-inch tart pan with removable bottom or a 9x13 cake pan and set aside.
Mix the flour, baking powder, salt and sugar in a large bowl. In another bowl, whisk together the buttermilk and eggs. Now, with one hand whisking the mixture, drizzle in the melted butter. You need to do this to keep the heat of the butter from scrambling the eggs.
Pour the wet ingredients into the dry ones, and mix just to combine. About halfway through the mixing, add the lemon zest and 1/2 cup of the huckleberries. Pour the batter into the tart pan and make sure it's evenly distributed. Sprinkle the remaining huckleberries over the cake, then the maple sugar.
Bake for 20-25 minutes, or until a toothpick comes clean out of the center of the cake. Gently remove the tart pan from the oven and set on a rack. Let this sit 5 minutes, then, very gently, pop the bottom up from the pan to free the cake, which will look like a large, flat muffin. If it sticks on the sides of the pan, use a knife to free the cake. Let the cake rest on the rack for 15-20 minutes before eating.