Preparation Steps
Preheat oven to 350 F.
Mix beans, oil, applesauce, eggs, egg yolk, sugar, cocoa powder, and espresso powder in your food processor.
Pulse for 1 minute, or until smooth.
Place your chopped chocolate and butter in a small bowl and microwave for 1 minute, stirring halfway.
Stir until the mixture is smooth.
Set aside to cool for a few minutes.
Add chocolate/butter mixture, vanilla extract, and salt to the food processor; pulse to blend.
Pour batter into a large bowl and stir in the flour.
Spread batter into a foil-lined 8x8" baking pan coated with nonstick cooking spray.
Smooth the top and sprinkle evenly with the walnuts (if using).
Bake for 25 to 30 minutes, or until a toothpick inserted into the center comes out clean.
Let the brownies cool in the pan on a wire rack for 15 minutes.
Cut into squares and serve.