It doesn't get any better than chocolate peanut butter oatmeal cookie bars! To put it simply, they're are the perfect cookie bar. Soft and chewy. Packed with peanut butter and stuffed with chocolate. This small batch recipe is easy to make from scratch, and after one bite you'll wish you'd made a bigger batch!
I think we're all in the mood for comfort food right now, and, for me, these soft and chewy cookie bars are just that. Peanut butter and chocolate are basically my happy place, and anything that feels like an upgraded chocolate chip cookie is exactly what I want to be baking.
These chocolate peanut butter oatmeal cookie bars are packed with peanut butter flavor and are super chewy thanks to oats, brown sugar, and egg yolk. Plus they are literally stuffed with chocolate; the cookie dough is full is chocolate chips AND there's a ribbon of rich chocolate filling running through the center of the bars. It's heaven on earth, friends!
Since these cookie bars are truly indulgent, and since most of us are currently baking for only ourselves or our households, I designed this small batch recipe to make just 8 cookie bars. If you'd prefer a larger batch, this can be easily doubled and baked in an 8 in. x 8 in. pan, and I've included instructions in the recipe notes. If you're sticking with the small batch recipe, here's exactly how I did it (using tools I already had available in my kitchen):
How to Bake Small Batch Cookie Bars
Fun fact: almost any bar recipe (brownies, cookie bars, etc.) that's baked in an 8 in. x 8 in. pan can be cut in half and baked in a loaf pan. Instant small batch recipe! A standard loaf pan is 8.5 in. x 4.5 in., which is just slightly larger than half the area of an 8x8 pan. I baked these chocolate peanut butter oatmeal cookie bars in a loaf pan in order to have just 8 reasonably-sized bars.
Just like with a standard size recipe, you'll want to line your loaf pan with parchment paper before baking. Check out this post for my easy and effective method for lining pans with parchment paper (I used the same method to line the loaf pan that I use for an 8x8 pan).
When you're ready to begin baking, this from-scratch recipe is super simple!
- Whisk together the dry ingredients: flour, oats, baking powder, baking soda, and salt.
- Separately, combine the wet ingredients and sugar: melted butter, brown sugar, peanut butter, egg yolk, and vanilla extract.
- Fold the dry ingredients into the wet ingredients. Then stir the chocolate chips into the cookie dough.
- Make the chocolate filling by combining melted butter and chocolate spread before mixing in confectioners' sugar.
- Press half of the cookie dough into a parchment-lined loaf pan. Spread the chocolate filling over the dough and top with the remaining cookie dough.
- Bake, let cool, and enjoy!
Small Batch Chocolate Peanut Butter Oatmeal Cookie Bars
Peanut Butter Oatmeal Cookie Dough:
- 9 Tablespoons all-purpose flour
- ⅜ cup old-fashioned oats
- ¼ teaspoon baking powder
- 1 pinch baking soda
- 1 pinch fine sea salt (plus more for sprinkling on top)
- 3 Tablespoons unsalted butter
- ½ cup light brown sugar
- 3 Tablespoons creamy peanut butter
- 1 egg yolk
- ½ teaspoon vanilla extract
- ½ cup semi-sweet chocolate chips plus more for topping bars
for the chocolate filling:
- 1 Tablespoon unsalted butter
- ¼ cup chocolate spread*
- ½ cup confectioners' sugar
- Preheat the oven to 350ºF. Line a standard loaf pan (8.5 in. x 4.5 in.) with parchment paper and set aside.
Make the cookie dough.
- In a small bowl, whisk together flour, oats, baking powder, baking soda, and salt. Set aside.
- Melt butter in a large, microwave-safe bowl. Add brown sugar and peanut butter and stir until blended and smooth.
- Add egg yolk and vanilla to the butter mixture and whisk until combined.
- Add the flour mixture to the butter mixture, and fold in the dry ingredients just until combined.
- Add the chocolate chips and stir until evenly distributed throughout the dough. Set the dough aside.
Make the chocolate filling.
- Melt the butter in a small, microwave-safe bowl. Add the chocolate spread and whisk to combine. Slowly add the confectioners' sugar, stirring to combine.
Bake the bars.
- Press half of the dough into the prepared pan. Use an offset or mini spatula to spread the chocolate filling over the dough in an even layer. Break up the remaining cookie dough into small, blackberry-sized pieces and scatter them over the chocolate filling so that it's completely covered. Sprinkle a few extra chocolate chips and a pinch of salt over the top.
- Bake for 20 minutes or until the edges are a light golden brown and a toothpick inserted into the bars comes out with just a few moist crumbs. Let the bars cool in the pan on a wire rack before removing them from the pan. Slice into 8 squares to serve.