For the Toffee:

 Set out a metal baking sheet. In a heavy-bottomed pot, combine the butter, sugar, salt, and water.  Heat on medium, stirring with a wooden spoon constantly as the butter and sugar melt and begin to bubble. Continue cooking and stirring for about 10-15 minutes, or until the mixture has reached 300 degrees on a candy or instant-read thermometer.  If you don’t have a thermometer, it is ready when the mixture is the color of a raw almond skin.

When it has finished cooking, pour the mixture onto the baking sheet and spread it out with the back of the wooden spoon.  When it has cooled and set, break and chop it into small pieces (about 1/4″ to 1/2″) and store in an airtight container until ready to mix into the cookies.

For the Cookies:

In a small saucepan, heat the butter over medium heat until it has melted and begun to foam. Gently scrape the bottom with a rubber spatula to prevent it from burning. Continue to cook until it has stopped making noise. The liquid will pop while it is cooking off but will be quiet once the butter has finished browning.

Begin by browning your butter (see the section below). Once it is browned, pour it into a mixing bowl or the bowl of a stand mixer and allow it to cool to room temperature. While it is cooling, measure out your other ingredients and chop the chocolate and toffee into small chunks, about 1/2″.

Using the paddle attachment on a stand mixer or a hand mixer, mix the browned butter until it’s broken up and fluffy.

Add the 1 cup of brown sugar and the 1/2 cup of white sugar to the butter and beat until well combined, about 2-3 minutes.

Add both of the eggs and stir in until well mixed.

Add the flour, baking powder and soda, and salt and beat on low until the flour is all incorporated.

Use a wooden spoon to stir in the chocolate and toffee chunks. The dough may seem stiff, but the butter will soften as they bake and the cookies should spread out nicely.

Portion out the cookie dough into 2 oz. balls and bake at 350°F for 10-11 minutes, or until the cookies are golden around the edges and still look a bit doughy in the center.

Remove the cookies from the oven and immediately use a table knife or the edge of a spoon to push any melted toffee that has misshapen the cookies back into a circle. Try to do this before the toffee cools and the sugar hardens again.

Allow the cookies to cool on the sheet for a few minutes, then remove them to a cooling rack to cool before eating. Store them in an airtight container at room temperature for up to a week. They will also freeze well.