Heat the water with the apple peels and bring to a boil. Remove from heat and discard the peels.
Add the oats to the water, stir, and let sit for 15 minutes.
Cream the butter with the two sugars and the eggs until light and fluffy.
Add the apple water and oat mixture and mix well. Set aside.
Combine flour, cocoa powder, baking powder, baking soda, and ground cinnamon, and add to the oat mixture. Incorporate. Mix in the diced apple and walnuts.
Spread the mixture in a greased and floured square pan of approximately 22 x 33 centimeters. Bake for 30-35 minutes or until a toothpick inserted comes out clean.
Let cool, top with whipped cream or powdered sugar, and cut into 5-centimeter squares.
Nutritional Information
* * Information per 100g serving, percentage of daily values based on a 2,000 calorie diet.
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