Just like the very best "kitchen sink" cookies, these bars live up to their name, packing in “everything but the kitchen sink” (plus, there’s no scooping or shaping required). Toss in the tail ends of a bag of chocolate chips, pretzels, crackers, or even cookie crumbs — the best version of these clean-out-the-pantry treats are salty, sweet, chewy, gooey, and crisp, all at once. They’ll satisfy your craving for something a little wild and wonderfully unexpected while embracing some no-waste creativity.
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Preheat the oven to 350°F. Line an 8" square pan with a parchment sling, then lightly grease the sides of the pan.
In a medium bowl, combine the graham cracker crumbs, melted butter, 1 tablespoon of the sweetened condensed milk, and the salt. Firmly press the mixture into the bottom of the pan; a flat-bottomed measuring cup or glass helps smooth the bottom. Set aside.
Crush half the potato chips (1 cup, about 32g) and half the pretzels (1/2 cup, about 28g) into fine crumbs. (It’s easy to do this in a sealed zip-top bag with a rolling pin or the bottom of a pot.)
In the now-empty bowl, combine the remaining sweetened condensed milk and the chip and pretzel crumbs. Pour this mixture over the crust and spread it into an even layer.
Sprinkle the chocolate chips evenly over the surface.
Top with the remaining potato chips and pretzels, then the additional sweet or salty mix-ins, followed by the sprinkles and flaky sea salt. Use your hands to lightly press all the mix-ins into the condensed milk mixture; it’s OK (even preferable) if some of the mix-ins stick up vertically.
Bake for 25 to 30 minutes, until the pretzels are a shade darker than they were before baking.
Remove the bars from the oven and allow them to cool in the pan on a rack for 1 to 1 1/2 hours, until they reach room temperature. Before serving, place the bars in the refrigerator to chill for 30 minutes, then remove them from the pan, slice, and serve. (The bars are easiest to cut when the crust and sticky filling are cold.)
Store leftover "Kitchen Sink" Cookie Bars in an airtight container in the refrigerator for up to 1 week; freeze for longer storage.
Tips from our Bakers
By definition, Kitchen Sink Cookie Bars offer a lot of flexibility when it comes to mix-ins. Here are a few guidelines to consider while experimenting:
We like this ratio of chips and pretzels, but you can customize it to your taste. Use about 3 cups (120g) total of your favorite salty, crunchy snacks.
For the final 1/4 cup (about 30g) of sweet or salty mix-ins, use any combination of graham snacks, crushed cookies, crackers, nuts, marshmallows, candy bars, large flake coconut, cereal, etc. We happen to like cheesy crackers and bear-shaped graham snacks.
