Step 1: In a medium skillet, melt 2 tablespoons of butter over medium heat. Add the diced apples and 2 tablespoons of granulated sugar. Cook, stirring occasionally, until apples are tender and lightly caramelized, about 8-10 minutes. Remove from heat and spread on a plate to cool completely.
Step 2: In a large bowl, cream together the remaining 14 tablespoons (1 3/4 sticks) softened butter, light brown sugar, and remaining 1/4 cup granulated sugar until light and fluffy, about 2-3 minutes.
Step 3: Beat in the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
Step 4: In a separate medium bowl, whisk together the all-purpose flour, ground cinnamon, baking soda, and salt.
Step 5: Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined. Do not overmix.
Step 6: Fold in the rolled oats and the cooled caramelized apples until evenly distributed.
Step 7: Cover the dough and chill in the refrigerator for at least 1 hour (or up to 24 hours). This step is crucial for texture!
Step 8: Preheat your oven to 375°F (190°C). Line baking sheets with parchment paper.
Step 9: Drop rounded tablespoons of dough onto the prepared baking sheets, spacing them about 2 inches apart.
Step 10: Bake for 10-12 minutes, or until the edges are golden brown and the centers are set. The cookies may still look slightly soft in the middle.
Step 11: Let the cookies cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely. Enjoy!