Step 1

In a medium-sized bowl, whisk together the flour, baking soda, cornstarch, and salt. Set aside.

Step 2

In a pan over medium heat, melt the butter, gently swirling the pan occasionally to make sure that the butter is being heated evenly. Cook until the foaming of the butter subsides. The butter should be warm brown in color and have a nutty smell. Transfer the butter to a heat-safe bowl to cool.

Step 3

In a large bowl, beat together the cooled brown butter and the sugars with a hand-mixer for about one minute. Then, add in the eggs and vanilla extract. Beat until just combined.

Step 4

Slowly add in the flour mixture and mix briefly, making sure not to overwork the cookie dough. Fold in about 3/4 of the pretzels, toffee chips, and caramels, reserving some of each to top after the cookies have baked.

Step 5

Cover and refrigerate the dough for 30 minutes to an hour, or until the dough is cold to the touch.

Step 6

Remove the dough from the refrigerator and preheat the oven to 325 degrees, making sure you have the racks in the middle of the oven. Line a baking sheet with parchment paper.

Step 7

Roll the cookie dough into ping-pong sized balls. Place on the prepared baking sheet, making sure the cookies have plenty of space to spread.

Step 8

Bake for about 12-15 minutes, rotating half-way through, or until the cookies have spread out and the edges are golden, but the center of the cookie still looks soft and just slightly under-cooked. Remove the tray of cookies from the oven, let cool for a minute or two, and then gently press a few of the reserved pretzel pieces, toffee chips, and caramels into the tops of the cookies. Continue to cool the cookies on the baking sheet until the cookies are firm enough to remove. Every oven is different, so I recommend starting with just one or two cookies on the tray to see what baking time works best for you!

Step 9

Repeat with remaining batches, until all cookies are baked.