Preheat oven to 350F. Line a 7x11 inch baking pan with foil or parchment paper, leaving a slight overhang.
Peel and finely dice the apple. Melt 1 teaspoon butter over medium heat in a small skillet. Add the apple and cook for one minute, tossing to coat with the butter. Sprinkle with 1/2 tablespoon brown sugar, 1 teaspoon cinnamon and 1 teaspoon flour and cook for another 2 minutes, carefully mixing until combined. Set aside to cool.
In a medium pot, melt 6 tablespoons butter over medium heat. Continue warming until the butter turns golden brown in color and starts smelling of hazelnuts. Whisk in 2/3 cup brown sugar and set aside to cool for 5 minutes.
Once the mix has cooled to room temperature, whisk in the oil, vanilla extract and the eggs. Evenly sprinkle the whole wheat flour on top, then the baking powder and salt. Carefully mix into the egg mixture until a batter forms. Fold in the apples.
Pour the batter into the prepared baking pan and sprinkle the top with chopped pecans.
Bake at 350F for 25-30 minutes or until they turn golden brown on top and a toothpick inserted comes out clean.
Cool in the pan on a wire rack before slicing into 12 squares.
To Make the Glaze
Sift the powdered sugar into a small bowl. Gradually stir in the apple juice, one teaspoon at a time, until it reaches the consistency of a thick glaze. It should be pourable, but not liquid. Drizzle over the cooled cake bars.
To freeze:Do not glaze the bars if you want to freeze them.Cut the cake into bars and place them into freezer-friendly storage containers. You can put parchment paper between the bars if you want to remove them individually.Alternatively, place single bars into small freezer bags.Make sure to label the containers or freezer bags with both their content and the date!Freeze the bars for up to a month.Thaw the bars in the fridge overnight. If you'd like to warm them up, do so in the microwave or for about 5 minutes at 300°F in the oven.
Serving: 1slice | Calories: 227kcal
Recipe created with ♡ for you by savorynothings.com