Preheat oven to 350°F (175°C). Grease and flour an 8x8 inch baking pan.
In a large bowl, combine the melted butter and brown sugar. Beat until smooth. Beat in the egg and vanilla extract.
In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Fold in the diced apples.
Pour the batter into the prepared pan and bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean.
Let the blondies cool completely before frosting.
For the maple glaze, melt the butter in a small saucepan over medium heat. Stir in the maple syrup. Remove from heat and whisk in the powdered sugar and milk until smooth.
Pour the glaze over the cooled blondies and let it set before cutting into squares.
Notes
Enjoy these delicious Maple Glazed Apple Blondies with a warm cup of coffee or tea!