Preheat the oven to 350 degrees, line an 8-inch square baking dish with foil and coat with cooking spray. Using a food processor, grind 1/2 cup almonds in 1-second pulses. Add the gluten-free flour, baking powder and salt and process briefly to blend. Transfer to a medium bowl.
Add the brown sugar, butter, eggs, applesauce and almond extract to the food processor and mix until smooth. Add the sugar mixture to the flour mixture and stir until blended. Stir in the chocolate and remaining 3/4 cup almonds.
Scrape the batter into the prepared pan and bake until lightly browned on the edges, 30 to 35 minutes. Let cool completely before cutting into squares.
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