Preheat oven to 350°F / 177°C.

Line two baking sheets with parchment paper or a baking mat like Silpat. (These will make it easiest to remove the cookies from the pan after baking.)

In a medium mixing bowl, whisk together flour, baking soda, and salt. Set aside.

In a stand mixer fitted with the paddle or using a hand mixer, beat together butter and both sugars until light and fluffy.

Add egg and vanilla extract and mix on low, scraping down the bowl as needed.

Add dry ingredients to mixer and mix on low just until everything is combined.

Stir in chocolate chips, toffee bits, potato chips, and pretzels.

Roll cookie dough into golf ball-sized balls. (Roll in extra toppings if you would like.) Spread cookie dough out on prepared pans, leaving about 6 inches between them.

Bake cookies until edges are crisp and centers are still soft, 10-12 minutes.

When you remove the cookies from the oven firmly tap the baking sheets on the kitchen counter to deflate them (this will make the centers soft). Sprinkle the cookies lightly with flaky sea salt (if using).

Allow the cookies to cool on the pan for 5 minutes before transferring to a cooling rack.

Store in an airtight container at room temperature for up to 1 week.