Peanut Butter Lover’s Cookie Bars

Name: Peanut Butter Lover's Cookie Bars
Prep time: 10 min
Cook time: 30 min
Total time: 40 min
Ingredients: ½ Cup Unsalted butter (room temperature); ¾ Cup Brown sugar; ¼ Cup Granulated sugar; 1 Egg; 1 tsp Vanilla extract; ½ Cup Creamy Peanut Butter; 1 ⅓ Cups All-purpose flour; 1 Tbsp Cornstarch; 1 tsp Baking soda; ½-1 Tbsp Milk; ½ Cup Mini Peanut Butter Cups; 3 Reese's Peanut Butter Cups (crushed); 1 Tbsp Creamy Peanut Butter; 1 Tbsp Milk; 1 Tbsp Butter; 2 Tbsp Confectioner's Sugar

January 7, 2020

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It may be a bit of an American stereotype, but I really just love peanut butter. There’s something special about the combination of roasty, salty, and sweet that just gets me every time. If you’re like me, always buying the biggest jar of the tasty sandwich spread, you will definitely enjoy these gooey treats. With quadruple pb-power, peanut butter cookie bars are for the real lovers of the stuff!

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Although there’s a little bit of chocolate, I really wanted the focus of this recipe to be on the peanut butter itself. It’s an homage to a true classic ingredient I have often fallen back on as I started eating less meat throughout my life. It has its place in savory dishes, but here it’s oh so sweet.

Between the peanut butter cookie base, the mini cups throughout, the crushed cups on top, and finally a gooey drizzle – that’s a lot of peanut butter. But these aren’t overwhelming. The other ingredients really help to balance out that nutty flavor, making for a true dessert treat.

What You Need to Get Started

You can easily find all of the ingredients for these peanut butter cookie bars at your grocery store. You can also order online using Amazon Pantry, or try Amazon Fresh for grocery delivery.

Fridge: Butter, Egg, Milk
Pantry: Brown sugar, Granulated sugar, Creamy peanut butter, All-purpose flour, Cornstarch, Baking soda, Mini peanut butter cups, Reese’s peanut butter cups, Confectioner’s sugar
Spice Rack: Vanilla extract
Equipment: 8×8 Baking pan, Parchment paper, Stand mixer, Mixing bowls, Whisk, Silicone spatula

Let’s Make Peanut Butter Cookie Bars

There’s nothing super complicated about these cookie bars. In fact, bars tend to be less work than cookies, because you bake it all at once for longer instead of doing batches. Plus, the outside ends up a bit more done than the middle, which means you can please chewy and crispy cookie lovers with one dish.

Before starting on the dough, preheat your oven and line a pan with parchment paper hanging over the edges, so the bars will be easy to remove and cut later. I used a glass pan, which tends to heat the edges more than the middle, for a dramatic difference. You can use a metal pan for less of a crust on these.

Begin the dough by creaming together butter and sugar in your stand mixer until it’s fluffy. Then you’ll mix in other liquid ingredients: peanut butter, vanilla, and eggs. I suggest using creamy peanut butter in this recipe, which will make for a nice, smooth dough.

Like most cookie recipes, use a separate bowl to whisk together all the remaining dry ingredients: flour, cornstarch, and baking soda. You might notice there’s no added salt here, which is because most peanut butters already contain plenty on their own. Mix it all together so there’s no baking soda pockets in your dough.

Add the dry ingredients to the mixer plus a little bit of milk, which will help the dough form together. You may need more milk depending on how your dough looks, so keep an eye on it while mixing. If it’s crumbly, add another splash. If it looks soft and doughy, you’re good.

Only mix the dough until it’s just combined, and there are no large lumps of flour. It’s always a good idea not to overmix cookie dough, which can make the cookie bars tough instead of gooey and chewy.

Once the dough is ready, add in the mini peanut butter cups to the bowl. And you can fill that measuring cup all the way, maybe a little bit heaping. Eat a couple too, I won’t tell anyone. Use a silicone spatula to fold the chips into the dough.

When you have a good distribution of peanut butter cups, it’s time to transfer the dough to your prepared pan. Use your silicone spatula again to scrape the bowl and get all that delicious, tasty dough into the pan.

Then gently press the dough, using your hands or the bottom of a measuring cup to push the dough into the shape of the pan. Be sure to get into all the corners, and be careful of any folds in the parchment.

Are you ready for peanut butter part three? It’s time to crush some Reese’s! I always keep a few of these in my freezer, but if you don’t, you may want to throw a couple in there a few hours before making these bars. They are easier to crush when slightly chilled.

I used a plastic bag and a wooden mallet to crush mine, but you can also break them apart with your hands, or use a rolling pin, the back of a heavy spoon, or even a knife to chop them.

Sprinkle the crushed cups evenly over the top of the dough, and give them a small press into the cookies, so they settle in nicely. Then you can place the entire pan in the freezer, covered loosely with some plastic wrap or foil and wait until it’s just a bit chilled.

Bake straight from the freezer if you’ve only left the pan in for ten minutes. If you want to prepare these ahead, you can freeze for longer. However, I suggest thawing the dough in the fridge overnight if you want to do that.

The cookie bars will be done after about 25-30 minutes. The best way to tell is to look for the dry edges, which will start to get a bit golden brown. Also, you can stick a toothpick right into the center.

It will look like the dough is still raw, but if the toothpick comes out clean, these are good to go. They’ll firm up a bit while they cool. In fact, you’ll want to let them set for about an hour before adding the drizzle on top.

To make the drizzle, use a small microwave-safe bowl to melt the butter along with some milk. Microwave in 15 second increments until the butter is melted. If it looks close, you can give the bowl a swirl, which will help it melt a bit faster.

Stir in the peanut butter until it’s nice and uniform. Then add the confectioner’s sugar in a little bit at a time, stirring until it’s smooth. The consistency should be fairly liquidy, but if needed, you can add a bit more warm milk.

Use the parchment paper to lift the cookie bars out of the pan and onto a cutting board. Then use a spoon to drizzle the topping over the bars. If you want more control over the look, feel free to use a pastry bag instead. Let it set for 5-10 minutes, then cut it into bars and serve.

Hey peanut butter lovers, these cookie bars are for you! With quadruple peanut butter goodness, you will love this sweet and gooey dessert.

How to Serve Cookie Bars

These cookie bars are best for dessert. Serve them with a glass of milk, or for something a bit warmer, try a chai white hot chocolate. If you’re looking for more of a kick, and want more peanut butter flavor, make some peanut butter cup boozy hot cocoa. Or for a little bit of contrast, try an amaretto old fashioned.

You can also add these to your next cookie tray. Include a few other options like cherry chocolate chip cookies, apple cider caramel stuffed snickerdoodles, plum jam newton-style cookie bars, and blueberry cheesecake cookies.

Use Up Leftover Ingredients

Peanut butter: Whip up the mousse filling for double chocolate cookie cups.
Mini peanut butter cups: These pair perfectly with miso in my favorite cookies.
Brown sugar: Use it in everything, especially a quick apple crisp.
Cornstarch: This helps add some fluffy to multigrain cocoa-cinnamon rolls.
Milk: Sour it up, and then use to make the biscuits atop a cherry cobbler.

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5 from 1 vote