Add butter to a saucepan over medium heat. Let the butter melt stirring occasionally, about 5 minutes.

When the butter begins to foam, stir every 30 seconds. When the butter is a deep rich amber color, remove from heat and pour into a bowl. Let cool for about 10 minutes.

While the butter is still slightly warm, add the espresso powder.

In a large bowl, mix together butter, sugar, and brown sugar until smooth and creamy.

Add in one egg and vanilla extract and mix together.

Add in flour and baking powder, mixing on low speed until combined.

Once the dry ingredients are almost mixed in, add in toffee bits and mix together.

Let dough chill for 30 minutes.

Preheat oven to 350 degrees.

Use a medium cookie scoop to scoop out the cookie dough and place on a parchment-lined baking sheet.

Bake for about 12-14 minutes; the centers will still be slightly gooey.

Let cool slightly, and enjoy!