In a small saucepan, pour in quality apple cider and bring it to a gentle boil over medium heat. Reduce to a simmer and let it cook for 15-20 minutes, stirring occasionally, until it thickens and reduces to about ¼ cup. Once finished, remove from heat and allow it to cool completely before incorporating it into your cookie batter.

In a skillet, melt unsalted butter over low heat, stirring constantly until it bubbles and turns a rich golden brown, about 5-7 minutes. Watch closely to prevent burning; the butter should have a nutty aroma. Once browned, let it cool slightly and then place it in the fridge for 15 minutes to firm up.

Combine all-purpose flour, baking powder, baking soda, cornstarch, apple pie spice, and salt in a mixing bowl. Whisk the dry ingredients until well combined.

In a large bowl, add the cooled brown butter along with granulated sugar and light brown sugar. Using a hand mixer, beat until light and fluffy. Then, add the egg, egg yolk, reduced cider, and vanilla extract, mixing smoothly.

Gradually add the dry ingredients to the wet mixture, stirring gently with a spatula until just combined. Let the dough rest at room temperature for about 30 minutes.

Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper. Use a cookie scoop to portion out dough balls, placing them on the baking sheet 3 inches apart.

Bake the cookies for 9-11 minutes until edges are set and centers remain slightly puffed. Let them cool on the sheet for 5 minutes before transferring to a wire rack.

Melt additional butter in a small bowl. Brush warm cookies with melted butter, then roll them in a mixture of granulated sugar and cinnamon.

Whisk together powdered sugar, vanilla extract, and reduced apple cider for the glaze until smooth. Drizzle over cooled cookies.