These Peanut Butter Cookie Bars will have your mouth watering, thinking of this dense, delicious combination of chocolate and peanut butter.
This recipe for easy peanut butter cookie bars is going to delight you with how easy they are to make. That's because these Peanut Butter Bars are made with a yellow cake mix, creamy peanut butter and a chocolate frosting that will make you swoon!
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Why should you make cookie bars instead of cookies?
Of course I really do love cookies! Cookies are actually one of my favorite baked goods, especially chocolate chip cookie. But COOKIE BARS are just so much more fun! I mean, duh, cookie bars are bigger, thicker, denser - and packed full of more flavor! If you love the flavor of Reeses peanut butter cookies, or nutter butter bars, but wish they had more chocolate, then this peanut butter bars recipe is for you!
Our peanut butter cookie bars recipes is going to quickly become one of your favorite family recipes! Do you remember the old fashioned peanut butter bars recipe our grandmas use to make? If you love peanut butter, you are going to love these peanut butter bar cookies!
Related Blondies, Brownies and Bars Recipes
Are you looking for other blondies, brownies or bars recipes like this peanut butter cookie bars recipe? Try these tried and true family favorite recipes, like our brown sugar shortbread cookie recipe.
These Peanut Butter Cookie Bars are Perfect for Any Occasion
These peanut butter cookie bars can be served as a snack or an after dinner treat. They taste just like chocolate cookies and peanut butter cookies combined. But this easy peanut butter cookie bar recipe requires way less effort because of our secret time-saving ingredient. Yep, we are talking about the box of yellow cake mix!
This recipe for peanut butter cookie bars might be my new go to recipe, whereas it is usually brownies. These chewy peanut butter bars are just so tasty and so rich! This easy easy peanut butter bars recipe makes an entire 9x13 pan, so you get about 35 bars! Trust me, they will go quick no matter where you take them - or if you just enjoy them at home!
How to Make Our Peanut Butter Cookie Bars
These peanut butter cookie bars are the perfect treat to share with your family and friends! If it is safe to provide peanut butter treats, of course! Make sure that no one has peanut allergies prior to inviting them to take a bite! You will find that our favorite recipe peanut butter cookie bars makes amazing peanut butter squares that your entire family will love!
Peanut Allergy Tip: If you need to make these peanut butter cookie bars allergy-safe, you can use any of these substitutes for Peanut Allergies. They will not taste the same as peanut butter, of course. But they are safe for folks who want to enjoy delicious cookie bars!
- Almond butter
- Sunflower butter
- Pecan butter with cashews
- Hazelnut butter
Here are the Ingredients that you will need to make our Peanut Butter Cookie Bars Recipe
- Package of yellow cake mix (this will be your only dry ingredients for this recipe and eliminates the need for baking soda)
- Unsalted butter at room temperature
- Creamy peanut butter - we like a natural peanut butter when just eating it alone, but it is a bit too oily for this recipe
- Eggs at room temperature
- Semi sweet Chocolate chips - we really love the Ghirardelli brand of semi sweet chocolate chips, but we also use Nestle Tollhouse a lot
- Sweetened condensed milk
- Pure Vanilla extract
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Directions for how to make our Peanut Butter Chocolate Bars Recipe
The first step you will take for our instructions preheat oven to 325 degrees Fahrenheit.
In a large mixing bowl, add together your box of yellow cake mix, unsalted butter, the cup creamy peanut butter and the eggs.
Mix all of these ingredients together with beater on low to medium speed for about a minute. Make sure that all of the ingredients are completely combined.
Set aside 1-½ cups of your cookie bar batter.
With the remaining cookie batter, you are going to evenly press the cookie dough into a 9x13 baking pan using your fingers. This batter is more like a dough, and it will be a little thick. Please make sure that you are not leaving any gaps in the cookie dough.
On the stove top, melt the chocolate chips along with the sweetened condensed milk and pure vanilla extract. Use medium heat and stir constantly so the chocolate doesn't burn. When completely melted, remove from heat and pour into 9x13 pan. Spread chocolate evenly.
Using the reserved cookie dough batter, now place the cake mixture on top of the chocolate. I used my fingers to grab a small chunk of batter and place on top of the chocolate.
Bake your Peanut Butter Cookie Bars in the oven for 20 to 25 minutes. Remove them from the oven and allow them to cool completely before cutting them into peanut butter squares.
Substitutions and Variations for this peanut butter bar recipe
Now, don't get me wrong! This Recipe for peanut butter cookie bars is perfectly delicious just as it is. However, I know that some folks like to get creative when trying new recipes and that is okay! Here are a few ideas for switching things up.
- Peanut butter chips - add ⅓ cup of peanut butter chips into the cookie dough before you put it into the oven.
- Peanut butter chocolate chip - You can add ¼ cup of mini chocolate chips on top of the cookie bars before they go into the oven to make this more of a peanut butter chocolate chip bars recipe!
- cup peanut butter - you can replace the creamy cup peanut butter with crunchy for a little twist on this recipe!
- peanut butter cornflake bars - You can add ½ cup of corn flakes to the cookie dough when you are done with the mixing process to give these bars a bit of crunch!
If you love all things chocolate, then I think you should also check out this really easy to make Chocolate Pecan Toffee recipe. We LOVE chocolate around here, especially when it is an easy to make recipe!
FAQs about making Peanut Butter Cookie bars
Should you refrigerate peanut butter cookie dough before baking it?
Normally we recommend chilling peanut butter cookie dough for several hours before baking to prevent them from spreading on the cookie sheet. However, this cookie bar dough is very solid and does NOT need to be refrigerated.
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I know that many people still like to print out recipes and keep them in a recipe binder, or simply have the printed recipe sitting in front of them when it comes time to cook!
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Peanut Butter Cookie Bars
- 1 box yellow cake mix
- ½ cup melted butter
- 1 cup peanut butter creamy
- 2 eggs
- 1 pkg chocolate chips
- 1 can sweetened condensed milk
- 2 teaspoons vanilla
- Heat oven to 325.
- In a mixing bowl, add cake mix, butter, peanut butter and eggs. Mix with beater for about a minute, combining all ingredients well. Set aside 1-½ cups batter. Evenly press remaining batter into a 9x13 pan using your fingers.
- On the stove, melt chocolate chips, sweetened condensed milk and vanilla. Use medium heat and stir constantly so the chocolate doesn't burn. When completely melted, remove from heat and pour into 9x13 pan. Spread chocolate evenly.
- Using reserved batter, place cake mixture on top of chocolate. I used my fingers to grab a small chunk of batter and place on top of the chocolate.
- Bake 20-25 minutes. Cool completely.
- To cut into bars: Use a metal spatula and loosen the bar edges all the way around the edge of the pan. Cut into about 35 bars (5 rows x 7 rowand serve. I found a sharp knife to be the best way to cut, and dragging it seemed to work well. Store covered if not serving right away.