Preheat your oven to 350°F (175°C) and prepare baking sheets lined with parchment paper.

In a large mixing bowl, cream together softened unsalted butter, granulated sugar, and brown sugar until light and fluffy.

Add eggs one at a time and mix, then add vanilla extract and blend until smooth.

In a separate bowl, whisk together flour, baking soda, cinnamon, and salt. Gradually add to wet ingredients and mix until just combined.

Fold in the diced apples and optional walnuts gently with a spatula.

Drop dough balls onto prepared baking sheets, spacing them 2 inches apart.

Bake for 12-15 minutes until edges are golden and centers are soft. Cool briefly on sheets before transferring to a wire rack.

In a medium bowl, whisk together powdered sugar, maple syrup, and milk until smooth. Adjust consistency as needed.

Drizzle the cooled cookies with maple glaze and let set for a few minutes before serving.