Dessert--German Dark Chocolate Fudge Brownies with Black Cherry Preserves

3 (3.5-ounces each) packages German dark chocolate (e.g., Vivani or Ritter Sport)
1/4 cup German black cherry preserves (e.g., Zentis)
3 tablespoons German spiced apple butter (e.g., Grafschafter)
2 tablespoons German Acacia honey (e.g., Langnese)
1 large egg
2 large egg whites
1 teaspoon fine sea salt1 teaspoon pure vanilla extract
1/2 cup all-purpose, unbleached flour*
1/4 cup chopped walnuts

Preheat oven to 350°F. Break or cut chocolate into 1-inch pieces and place in heatproof bowl.

Gently melt chocolate in double boiler. Remove from heat; set aside. Coat an 8-inch square non-stick baking pan with cooking spray; set aside. In large bowl combine preserves, apple butter, honey, eggs, egg whites, salt and vanilla extract. Whisk to thoroughly combine. Whisk in flour until smooth. Slowly pour melted chocolate into batter, whisking continuously. Spread batter in pan. Sprinkle with walnuts. Bake 20 minutes or until springy to the touch. Cool on rack. Cut into 24 bars. Serves 24 (1 brownie/serving)

*Option: Mixture of 1/4 cup all-purpose, unbleached flour and 3 tablespoons whole-wheat flour.