Blackberry Financier - unsalted butter

Method

• In a saucepan, melt the butter over medium heat.
• The butter will separate into melted golden fat and white, grainy milk solids.
• Cook until the milk solids turn golden brown and the mixture smells like toasted nuts, making "beurre noisette".
• Strain through a fine sieve to remove the milk solids.
• Sift the dry ingredients together and place in a mixer fitted with a whip attachment.
• Add the egg whites, applesauce and strained beurre noisette and mix.
• The batter can be made to this point up to 3 days in advance.
• Keep refrigerated.
• When ready to bake, butter tiny rectangular or round tart molds and cut the blackberries in half, top to bottom.
• Preheat the oven to 375 degrees F.
• Transfer the batter to a pastry bag fitted with a large plain tip and pipe into the prepared molds.
• Place 1/2 of a blackberry in the center of each mold, cut side down.
• Bake for 10 minutes, until golden brown.
• Let cool in the molds, then gently lift the cakes out.
• Sprinkle with powdered sugar and serve.