Make your afternoons sweet with these super-easy chunky cookie bars.
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Need a weekend baking project that doesn’t overly tax your brain or time? Craving a homey tray bake of sliceable goodies that are easy for snacking? At your limit in terms of both time and energy? Let a good old box of cake mix come to your rescue. Because you can turn any flavor of cake mix into chunky sliceable bars with minimal effort and maximum pleasure. It’s the ultimate snack hack!

How to Make Snack Bars with Boxed Cake Mix

It could not be easier. Ready?

Heat your oven to 350, and line a 9x13 pan with either foil or parchment paper and lightly spray with nonstick baking spray. I like to make a sort of sling out of the foil or paper to make it easy to remove the bars from the pan.

Here’s what you’ll need:

  • 1 15.25-ounce box of any flavor cake mix
  • 1 stick of melted butter or a half cup of oil of your choice
  • 2 large eggs
  • 2 cups mix-ins

Beat the eggs with the oil and then add to the dry mix and blend till combined. Now the fun part: the mix-ins! Here is where you can use up those little ends of bags of things like chocolate chips, shredded coconut, chopped nuts, dried fruits, even the last bit of cereal or chips in the bottom of the box or bag! You can go all one flavor, or a mishmash. Whatever you like in your bars, toss it in there.

Spread your dough carefully into your prepared pan—I often use a large scoop to put the dough into the pan a little evenly so that I don’t have to mush it around too much. If you want a swirl of something like peanut butter or caramel or jam, go for it! Add a streusel topping or a layer of granola, sprinkle on some flaky sea salt, whatever you like!

Bake for about 16-20 minutes, until lightly golden and firm around the edges.  It is possible the very center might look slighty underbaked, but it will finish cooking as it rests, and give a nice chew.

Cool completely in the pan on a rack before slicing into bars, which you can do in the pan or using the parchment or foil to remove as a slab and then slicing.  Keep in an airtight container at room temp for up to 5 days, or wrap in plastic wrap and then foil, and put in a freezer bag and freeze for up to three months.

Stack of cookie bars

The best cake mix to use

I use Duncan Hines brand almost exclusively. They have a huge range of fun flavors, and I love the results I get with their products, whether I am using them for actual cake or as an ingredient in another recipe. If you have another brand, this recipe will work as long as it is 15.25 ounces.

Great cake mixes and mix-in combos to try!

This recipe is so easy, it can be really fun to begin playing with options. Here are some of my favorite cake mix/mix-in combinations to get you going.

Devil’s food cake mix with crushed pretzels, chopped peanuts, and peanut butter swirl

Banana cake mix with chopped banana chips and chocolate chunks

Vanilla cake mix with mini caramels and dried apple pieces

Golden cake mix with toasted chopped hazelnuts and dried cherries