Brown the butter by melting it on medium heat in a light-colored pan until it foams, settles, and turns golden brown, stirring continuously. This takes about 5 to 8 minutes.

Pour the browned butter into a heat-safe bowl, scraping in the brown bits, and let it cool for about 15 to 25 minutes.

Stir in the brown sugar and white sugar into the cooled butter until smooth and glossy.

Mix in the eggs one at a time, then add the vanilla. The dough will look thick and shiny.

Add flour, baking soda, and salt, mixing just until no dry flour is visible.

Fold in chocolate and toffee bits, being careful not to overmix. Save some to press on top of the dough balls.

Chill the dough in the refrigerator for at least 45 minutes to keep cookies thicker and enhance flavor.

Scoop dough onto a lined baking sheet and bake at 350°F for about 10 to 12 minutes until the edges look set and the centers look slightly underdone.

Let the cookies cool on the baking sheet, as they will continue to cook as they cool down.