1. Step 1: Prepare the Pecans Preheat your oven to 350°F (175°C). Spread the pecans on a baking sheet in a single layer and toast for 6-8 minutes until fragrant and slightly darkened, stirring once halfway through. Let them cool completely, then chop them coarsely, leaving some larger pieces for texture.

Step 2: Brown the Butter In a medium saucepan over medium heat, melt the butter, stirring occasionally. Continue cooking as it foams, watching carefully until it turns amber and smells nutty, about 5-7 minutes. Immediately transfer to a heat-proof bowl and let cool for 10 minutes.

Step 3: Mix Wet Ingredients Add both sugars to the browned butter and beat for 2 minutes until well combined. Add eggs one at a time, mixing thoroughly after each addition. Stir in the vanilla extract, mixing until the batter looks smooth and glossy.

Step 4: Combine Dry Ingredients In a separate bowl, whisk together the flour, baking soda, and salt (plus cinnamon if using). Gradually add this mixture to the wet ingredients, stirring just until no dry streaks remain. Fold in the toasted pecans and toffee bits (if using) with a rubber spatula.

Step 5: Chill and Prepare for Baking Cover the dough and refrigerate for at least 1 hour or up to 24 hours. When ready to bake, preheat your oven to 350°F (175°C) and line baking sheets with parchment paper. Roll the dough into 1½-inch balls (about 2 tablespoons each) and place 2 inches apart on the prepared sheets.

Step 6: Bake to Perfection Bake for 11-13 minutes, until the edges are set and lightly golden but the centers still look slightly underdone. Don’t overbake! Let the cookies cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely. They’ll continue firming up as they cool while maintaining that perfect chewy center.