Begin by browning the butter. In a nonstick, heavy-bottomed pot, melt the butter over low to medium heat. Once melted, it will start to crackle. Stir the butter continuously and keep a close eye on it to prevent burning. You'll know it's ready when it develops a nutty aroma and turns a light brown or amber color. Remove from heat and transfer the butter, including the brown bits, to a large heatproof bowl. The browned butter should weigh about 108g.

In a medium bowl, mix together the flour, baking soda, and salt to create your dry ingredients.

Add the light brown sugar and granulated sugar to the bowl with the browned butter. Use a spatula or large spoon to combine the sugars with the butter, allowing it to cool slightly. Ensure the mixture is warm but not hot to the touch before adding the egg.

Quickly mix in the egg, followed by the vanilla extract, until the mixture is smooth and thick.

Gradually fold the dry ingredients into the wet mixture until a shaggy dough forms. Then, incorporate the ¾ cup (120g) of toffee bits, mixing until they are evenly distributed throughout the dough.

Cover the unscooped dough and place it in the fridge to chill for 15 minutes. Avoid chilling for longer than 30 minutes unless covered with plastic wrap.

In a small bowl, set aside the 2 tablespoons (20g) of toffee bits for topping.

On a lined cookie sheet, use a cookie scoop or large spoon to portion out the dough, aiming for about 10 cookies, each weighing approximately 60g (3 tablespoons). Roll each portion into a smooth ball and sprinkle the tops with the reserved toffee bits.

Return the dough balls to the fridge to chill for about 45 minutes. If chilling for longer than an hour, cover with plastic wrap to prevent drying out.

When ready to bake, preheat your oven to 350 degrees Fahrenheit. Arrange the dough balls on two large, parchment-lined cookie sheets, spacing them out. Bake one sheet at a time for 11-13 minutes, or until the edges are golden.

Allow the cookies to cool for at least 15 minutes before enjoying.