In a medium saucepan over medium heat, melt 1 cup of unsalted butter until it starts to bubble. Stir frequently until it turns golden brown and emits a nutty aroma—about 5–7 minutes. Let cool to room temperature.

In a large mixing bowl, combine the cooled brown butter, 1 cup of brown sugar, and 1/2 cup of granulated sugar. Mix until smooth and creamy.

Add 2 large eggs, one at a time, mixing well after each addition. Then, add 1 teaspoon of vanilla extract.

In a separate bowl, whisk together 2 1/4 cups of all-purpose flour, 1 teaspoon of baking soda, and 1/2 teaspoon of salt. Gradually add to the wet ingredients, mixing on low.

Fold in 1 cup of toffee bits and optional 1/2 cup of chocolate chips with a spatula.

Wrap the dough in plastic wrap or place it in an airtight container, then refrigerate for 30-60 minutes.

Preheat your oven to 350°F (175°C) and line two baking sheets with parchment paper.

Drop rounded mounds of dough onto the prepared sheets, leaving about 2 inches of space between each.

If desired, sprinkle a pinch of flaky sea salt on top of each mound before baking.

Bake for 10-12 minutes until edges are golden and centers are slightly soft.

Let the cookies cool on the sheets for about 5 minutes before transferring to a wire rack.