Melt the stick of butter in a pan over medium heat. Once the butter has completely melted and begins to lightly bubble, begin to swirl the pan. Continue to swirl the pan while the butter cooks. The butter will foam and then, as the foam subsides, the milk solids in the butter will begin to turn a golden brown color. Once the milk solids are golden brown and smells distinctly buttery and nutty, immediately remove the butter from the heat and pour into a heat prove bowl. Cover the butter and refrigerate until it reaches a softened butter consistency.
In a mixing bowl, combined softened browned butter, brown sugar, egg, egg yolk, maple syrup and vanilla. Whisk until all the wet ingredients are homogenous.
To the wet ingredients, add flour, baking soda, cinnamon and salt. Gently fold the dry ingredients into the wet ingredients with a wooden spoon just until combined. Cover the mixing bowl with plastic wrap and refrigerate dough for one hour or up to overnight.
When you are ready to bake the cookies, preheat the oven to 350°F and line two baking sheets with parchment paper. Scoop cookie dough using a 2 tablespoon cookie scoop onto the parchment lined baking sheets. Bake cookies at 350°F for 12 minutes.
While the cookies are baking, make the maple glaze by combining softened butter, maple syrup, powdered sugar and a pinch of salt. Whisk ingredients together until a smooth glaze forms.
Allow cookies to cool for a few minutes before transferring to a wire rack to cool completely. Once the cookies are cool, drizzle with maple glaze.