Step 1: Preheat Your Oven. Start by preheating your oven to 410°F (210°C). This higher temperature will help achieve that signature crispy edge while keeping the center soft.
Step 2: Cream the Butter and Sugars. In a large mixing bowl, add the cold butter cubes, granulated sugar, and light brown sugar. Using a stand mixer or hand mixer, cream the mixture together until it is light and fluffy, which should take about 2-3 minutes.
Step 3: Add Eggs. Beat in the two large eggs, one at a time, ensuring each egg is fully incorporated before adding the next. This step adds moisture and richness to your dough.
Step 4: Combine the Dry Ingredients. In a separate bowl, whisk together the cake flour, all-purpose flour, kosher salt, cornstarch, baking powder, and baking soda. This mixture will ensure that the leavening agents are evenly distributed throughout the dough.
Step 5: Mix Dry Ingredients into Wet Ingredients. Gradually add the dry mixture to the wet ingredients, mixing gently until just combined. Be careful not to overmix; it’s okay if there are a few flour streaks remaining.
Step 6: Fold in the Chocolate and Nuts. Using a spatula, fold in the semi-sweet chocolate chips, grated chocolate, and chopped walnuts. The chocolate will melt slightly into the warm dough, creating pockets of gooey goodness.
Step 7: Scoop the Dough. Using a large scoop or ice cream scoop, portion out the dough onto your prepared baking sheet. Leave enough space between each cookie since they will spread while baking. Aim for about 6 cookies per sheet.
Step 8: Bake. Place the baking sheet in the preheated oven and bake for 10-12 minutes. The cookies should be golden brown on the edges but still soft in the center. Remember, they will continue to cook slightly after being removed from the oven.
Step 9: Cool and Enjoy. Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely. Enjoy them warm or at room temperature!
