1. Brown the Butter: The Key to Unforgettable Flavor

1. Melt Butter: In a medium saucepan over medium-low heat, melt the 1 cup of unsalted butter.
2. Cook and Watch Closely: Continue to cook, swirling the pan occasionally, until the butter begins to foam. This indicates that the water content in the butter is starting to boil off.
3. Watch for Brown Specs: As the butter cooks, you’ll start to see tiny brown specks of milk solids forming at the bottom of the pan. These are the key to the browned butter flavor. Stir and scrape the bottom of the pan with a spatula to prevent them from burning.
4. Achieve Chestnut Brown Color: Continue cooking and stirring until the butter turns a rich chestnut brown color and emits a nutty aroma. This should take about 6-7 minutes.
   • Tip: Be patient and don’t rush this process. Browning the butter takes time, but the flavor it adds is well worth the wait.
5. Remove from Heat: As soon as the butter is browned, immediately remove the pan from the heat to prevent it from burning.

2. Incorporate Sugars and Chill: Developing Flavor and Texture

1. Add Sugars: Add the brown sugar and granulated sugar to the warm, browned butter in the saucepan.
2. Stir Until Smooth: Stir vigorously until the sugars are fully incorporated and the mixture is smooth.
3. Chill: Transfer the mixture to the refrigerator and chill for about 10 minutes. This allows the butter to cool slightly and the flavors to meld.

3. Prepare for Baking: Getting the Oven and Baking Sheets Ready

1. Preheat Oven: While the butter mixture is chilling, preheat your oven to 325°F (165°C).
2. Line Baking Sheets: Line two baking sheets with parchment paper.

4. Combine Wet Ingredients: Adding Eggs and Vanilla

1. Remove from Refrigerator: After 10 minutes, remove the browned butter mixture from the refrigerator.
2. Stir in Eggs and Vanilla: Add the eggs one at a time, mixing well after each addition until fully incorporated. Stir in the vanilla extract.

5. Combine Dry Ingredients: A Separate Step for Even Distribution

1. Whisk Together: In a separate bowl, whisk together the flour, oats, baking soda, salt, and cinnamon.

6. Gradually Add Dry Ingredients to Wet Ingredients: Forming the Dough

1. Combine: With the mixer on low speed, gradually add the dry ingredients to the wet ingredients, mixing until just combined. Be careful not to overmix.

7. Fold in Chocolate Chips: Adding the Sweet Indulgence

1. Add Chocolate Chips: Gently fold in the white chocolate chips and semi-sweet chocolate chips using a rubber spatula until they are evenly distributed throughout the dough.

8. Scoop and Shape the Cookies: Preparing for the Oven

1. Scoop Dough: Using a 2-tablespoon cookie scoop (or a spoon), scoop out portions of the cookie dough.
2. Place on Baking Sheets: Place the dough portions onto the prepared baking sheets, leaving about 2 inches between each cookie to allow for spreading.
3. Flatten Slightly: Using your hand or the bottom of a glass, gently press each cookie down slightly to flatten it a bit. This will help them bake evenly.

9. Bake to Perfection: Achieving the Ideal Texture

1. Bake: Bake for 11-13 minutes.
   • Check for Doneness: The cookies are done when the edges just start to turn golden brown. The centers should still be slightly soft. Do not overbake, or the cookies will be dry.
2. Cool: Remove the baking sheets from the oven and let the cookies cool on the sheets for a few minutes before transferring them to a wire rack to cool completely.