Peel and finely dice the Gala apples. In a skillet, combine with dark brown sugar, ground cinnamon, salt, and lemon juice. Cook for about 10 minutes until apples are browned and soft. Chill.

Melt unsalted butter in a saucepan over medium heat, stirring until it turns golden brown and nutty. Cool in the fridge for about 10 minutes.

In a bowl, whisk together all-purpose flour, baking soda, cream of tartar, ground cinnamon, fine sea salt, and cornstarch. Set aside.

In another bowl, whisk the cooled brown butter with dark brown sugar and granulated sugar. Add vanilla, an egg, and an egg yolk. Mix well and fold in the caramelized apples.

Gradually add the dry ingredients to the wet mixture, folding gently until a dough forms. Cover and refrigerate for 2-3 hours.

Preheat oven to 350°F (175°C) and line a baking sheet with parchment paper. Mix granulated sugar and ground cinnamon for the coating.

Scoop dough portions and roll into balls, then coat in the cinnamon sugar mixture. Place on the baking sheet, spaced apart.

Bake for 12-14 minutes until edges are set and tops are slightly puffed. Cool on pan for 5 minutes before transferring to a cooling rack.