Preheat the oven to 375°F. Line two baking sheets with parchment paper.
In a large mixing bowl with an electric mixer, or in the bowl of a stand mixer, beat together the butter and the sugars until they are creamy and combined, about 2-3 minutes using the paddle attachment of a stand mixer or an electric hand mixer.
1 cup salted butter, 1 cup light brown sugar, ½ cup granulated sugar
Add in the vanilla and the eggs and beat again, scraping the bottom and sides of the bowl until everything is evenly mixed together.
2 teaspoons vanilla extract, 2 large eggs
Stir the flour, salt, and baking soda into the wet ingredients and mix just until they are incorporated. It's okay if a few streaks of flour remain since the dough will continue being mixed together while adding the mix-ins.
2½ cups all-purpose flour, 1 teaspoon salt, 1 teaspoon baking soda
Add the milk chocolate chips, semi-sweet chocolate chips, crushed pretzels, potato chips, graham cracker pieces, and toffee bits into the flour mixture and stir just until evenly distributed.
1 cup milk chocolate chips, 1 cup semisweet chocolate chips, 1 cup crushed pretzels, 1 cup potato chips, 4 graham crackers, 1 cup toffee bits
Use a medium cookie scoop to scoop balls of cookie dough onto the cookie sheets lined with parchment paper. Space them about 1 to 2 inches apart to allow for spreading.
Bake the cookies for 10-12 minutes until golden brown and set around the edges. Top with the flaky sea salt. Let the cookies cool for 5 minutes on the baking sheet before transferring them to a cooling rack.
Flaky sea salt