1-First, prepare the peach filling to get that juicy center just right. Combine 4 large ripe peaches (diced, about 4 cups or 25 ounces), 1/4 cup granulated sugar, 1/4 cup plus 1 tablespoon light brown sugar (packed), 1 teaspoon lemon juice, 3/4 teaspoon cinnamon, and 1/4 teaspoon nutmeg in a medium saucepan over medium heat. Cook for 6 minutes until bubbly, then mix 2 teaspoons cornstarch with 2 teaspoons water, stir it in, and cook for 1 more minute. Remove from heat and add 1/2 teaspoon vanilla extract before cooling it completely in the fridge.

2-Next, make the cookie dough by creaming 1 cup softened salted butter with 1 cup granulated sugar and 1/2 cup light brown sugar (packed) using an electric mixer. Add 1 and 1/2 teaspoons vanilla extract and 2 large eggs, mixing until combined. In another bowl, mix 3 cups all-purpose flour (spooned and leveled or weighed), 1 teaspoon baking soda, 1 teaspoon baking powder, 1/4 teaspoon salt, 1 and 1/2 teaspoons cinnamon, and 1/2 teaspoon nutmeg, then add it to the wet ingredients to form a soft dough. Chill the dough for 30 minutes.

3-Scoop and Chill the Dough Scoop the chilled dough into balls about 55 grams each and roll them in a mixture of 1/2 cup granulated sugar, 2 teaspoons cinnamon, and 1/8 teaspoon nutmeg. Place them on a lined baking sheet and chill in an airtight container for at least 3 hours or up to 48 hours.

4-Prepare the crumble by mixing 1/4 cup melted salted butter with 1/3 cup light brown sugar (packed), 1/2 cup plus 1 tablespoon all-purpose flour, and 3/4 teaspoon cinnamon. Spread it on a parchment-lined baking sheet and bake at 350°F for 12-14 minutes until golden brown, then let it cool and break into small pieces.

5-Bake the cookies at 350°F for 11-13 minutes until the edges are set. Press an indent into the center of each cookie right after baking, then cool on the sheet before transferring to a wire rack. Finally, assemble by spooning in the peach filling, adding crumble, and drizzling with the optional glaze made from 1/3 cup powdered sugar, 1/4 teaspoon vanilla extract, a pinch of cinnamon, and 1-2 tablespoons milk.