Step by Step:

1️⃣ Prepare the Dough:

• Preheat your oven to 375°F (190°C). Line baking sheets with parchment paper.
• In a large bowl, cream together the cold butter, brown sugar, and granulated sugar using a stand mixer or hand mixer on medium speed until fluffy (about 2-3 minutes).

2️⃣ Add Wet Ingredients:

• Beat in the eggs, one at a time, followed by the vanilla extract.

3️⃣ Mix the Dry Ingredients:

• In a separate bowl, whisk together the all-purpose flour, bread flour, baking soda, cornstarch, and salt. Gradually add the dry mixture to the wet ingredients, mixing just until combined.

4️⃣ Fold in the Goodies:

• Gently fold in the chocolate chips and walnuts (if using).

5️⃣ Shape the Cookies:

• Scoop large portions of dough (about 1/4 cup each) and roll into balls. Place them 2 inches apart on the prepared baking sheets.

6️⃣ Bake to Perfection:

• Bake for 9-11 minutes, or until the edges are lightly golden, and the centers look slightly underbaked. This ensures they stay soft and gooey!

7️⃣ Cool and Enjoy:

• Let the cookies rest on the baking sheets for 10 minutes before transferring to a wire rack to cool completely.