Preheat oven to 350°F. Line a 9-inch square baking dish with parchment paper.

In a small bowl, toss diced apples with ground cinnamon and a tablespoon of flour. Set aside.

In a large bowl, mix melted butter and brown sugar until smooth. Add egg and vanilla, beat until combined.

Gradually add remaining flour and salt into the wet mixture. Mix just until incorporated.

Fold in diced apples and toffee bits. Pour batter into prepared pan and spread evenly.

Bake for 25 minutes or until a toothpick inserted in the center comes out clean.

Let blondies cool completely before preparing the glaze.

For the glaze, beat softened butter, powdered sugar, caramel sauce, and heavy cream until smooth and creamy.

Spread the caramel glaze over cooled blondies. Sprinkle additional toffee bits on top if desired.