Step 1Lightly grease a 4-quart (10-inch) Dutch oven. Prepare a batch of coals (at least 27) without starter fluid in a chimney starter until they are hot enough to have formed a thin coating of white ash over the surface of each coal. Alternatively, the dumplings can be baked using a greased 13-by-9-inch baking dish in a conventional oven heated to 425 degrees.
Step 2Combine the peaches and blackberries in the Dutch oven, and toss with 2 tablespoons maple syrup, the almond extract and orange zest.
Step 3In a large bowl, whisk together the flour, sugar, salt and baking powder. Cut in the cold butter using a pastry cutter or fork until the butter is reduced to small, pea-sized pieces. Pour in the buttermilk, and stir until the mixture is combined to form a thick, sticky batter. Gently stir in the almonds to combine.
Step 4Scoop the batter into 8 or so portions, using a large soup or small serving spoon. Space the dumplings evenly over the peaches and blackberries. Cover with the lid.
Step 5Place the Dutch oven over nine of the hot coals (evenly spaced), and evenly space 18 coals over the lid. Cook until the dumplings are puffed and a rich golden color and the fruit is soft, 20 to 25 minutes. If cooking in a conventional oven, bake the dumplings, uncovered, until puffed and golden, 30 to 35 minutes. Cool slightly before serving.