Peanut Butter Cookie Bars

These easy and foolproof cookie bars pack a ton of creamy peanut butter flavor and can be customized with bits of chocolate, candy, or peanuts.

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About Peanut Butter Cookie Bars

If you’re looking to cure your cookie cravings for a little less effort, look no further than these peanut butter cookie bars.

Because with a cookie bar, you get all the same tasty comfort of a freshly homemade cookie but without getting your hands dirty by scooping and rolling dough.

Cookie bars are all about simplicity. You only need to mix the ingredients, spread them into a pan, and bake. The bars still need to be cut, sure, but you can do that has you eat your way through the pan.

And with these bars having a hearty dose of peanut butter and chocolate, these baked treats are bound to be a go-to comfort food.

Do you have to use a jelly roll pan?

When baking cookie bars, you’ll commonly see “jelly roll pans” listed as the ideal type of pan to use in the recipe instructions. And if you’re not an avid baker, you might not have even known there was such a thing (hey, we were all there at one point).

So, what’s the difference between a jelly roll pan an a rimmed baking sheet? Is there a reason to use one and not the other?

In truth, jelly roll pans is just a term for a specific size of pan. It’s typically 10.5 x 15.5 inch in size and 1 inch deep. And as the name implies, this is usually the standard size for jelly roll cakes. However, these slightly less-traditional pans are also an ideal size for making most cookie bars, especially if you prefer the bars to have a rectangular shape. The pan dimensions make cutting the cookies easy to eyeball for a classic look.

But does that mean you have to use a jelly roll pan for cookie bars? Absolutely not! If you have a pan of similar length and width, and it has a rim that’s at least 1 inches deep, then it would be more than sufficient for use with this recipe.

How to cut perfect cookie bars

If you’re anything like me and get a little nervous when cutting food, fear not – there’s an easy trick you can use to get your cookie bars to have perfectly cut lines and dimensions.

The trick: Before adding your batter to the jelly roll pan, line it with aluminum foil, draping the edges over the sides of the pan. This will make it so you can simply lift the baked and uncut cookie bars from the pan, set it on the counter, and cut the bars without the sides of the pan interfering with your accuracy. You can even whip out a ruler if you’d like to make sure every bar is the exact size you’d like them to be.

See the below photo? Those perfect lines were a breeze to create using the above method.

How long do cookie bars last?

When stored in an air-tight consider, these peanut butter cookie bars should last about three days at room temperature.

As with most cookies, do not store cookies in the refrigerator. This does not extend their life; the bars will go stale much faster and lose their quality quicker when stored in cool temps.

Can you freeze peanut butter cookie bars?

If you’d like to always have a batch of these cookie bars on hand, the easiest way is to freeze them for later. There are two ways you can do this.

To freeze the raw dough: 

• Mix all ingredients per recipe instructions, then place the dough on a large piece of plastic wrap. Press the dough into a flat, log-like shape, then cover any exposed sides with plastic wrap.
• Transfer wrapped dough to a freezer bag or a storage container with a sealable lid.
• Dough can be stored for up to six months. When ready to bake, thaw in the refrigerator overnight, then prepare for baking per the recipe instructions.

To freeze baked cookie bars:

• Bake and allow to cool completely.
• If storing cut cookie bars, place them in a single layer in a freezer bag or storage container. If you need to stack the bars, separate each layer with a sheet of wax paper. If storing the uncut cookie bars, simply place in a freezer bag or storage container that they fit in.
• Baked cookie bars can be frozen for up to three months.

Do you have to use peanuts or chocolate?

This recipe uses some fun garnish to help amp up the flavor, but you can skip them if you’d like. You can also use other add-ins if you’d prefer, such as:

• M&M’s
• Reese’s Pieces
• Reese’s Peanut Butter Cups
• Cut up Snickers
• Other types of nuts, like walnuts or cashews
• Other types of chips, like white chocolate or caramel

Notes & tips for these peanut butter bars

• For this recipe, I highly recommend using a stand mixer or a hand mixer. The batter gets thick and could be difficult to mix by hand.
• As mentioned above, a jelly roll pan is the ideal choice for baking cookie bars.

More easy cake mix recipes

Other tasty peanut butter treats

How to make peanut butter cookie bars

This next part is only a photo tutorial of the recipe steps. If you’re looking for the full recipe measurements and instructions, scroll down to Recipe Details.

Step 1 – Using a stand mixer (or hand mixer + large bowl), whip up the following ingredients: eggs, water, butter, peanut butter, and 1/2 of the dry cake mix.

Step 2 – Add the remaining dry cake mix to the bowl, then mix until nice and smooth.

Step 3 – If you’re adding chips and peanuts, fold them into the dough.

Step 4 – Prepare a jelly roll pan by lining it with aluminum foil and spraying it with cooking spray, then pour the batter in. Spread the dough out into an even layer.

Step 5 – Bake!

Step 6 – Let cool completely before cutting into square or rectangular cookie bar shapes.