Irresistible Reese’s Pieces Cookie Bars have become my go-to dessert for family gatherings and potlucks! These delightful treats combine the perfect texture of chewy cookie bars with the irresistible candy-coated peanut butter goodness of Reese’s Pieces. If you’re a fan of Reese’s Pieces Cookies in their traditional form, you’ll absolutely fall in love with this convenient bar version that delivers the same amazing flavor but with even less effort.
Nutritional Benefits
While these cookie bars are definitely a treat, they do offer some nutritional benefits when enjoyed in moderation:
| Nutrient | Amount per Serving |
|---|---|
| Calories | 285 |
| Carbohydrates | 34g |
| Protein | 4g |
| Fat | 15g |
| Fiber | 1g |
| Sugar | 22g |
The peanut butter in these bars provides some protein and healthy fats, while the eggs contribute additional protein. When making these Irresistible Reese’s Pieces Cookie Bars, you can adjust ingredients to suit dietary needs while still maintaining that classic Reese’s Pieces Cookies flavor profile.
Ingredients & Substitutions

| Ingredient | Role | Possible Substitutions |
|---|---|---|
| 2 cups all-purpose flour | Structure | 1:1 gluten-free flour blend, whole wheat flour (slightly denser result) |
| 1 tsp baking soda | Leavening | 1 tsp baking powder (slightly cakier texture) |
| ½ tsp salt | Flavor enhancer | Sea salt or kosher salt |
| ¾ cup unsalted butter, melted | Moisture, richness | Coconut oil, vegetable oil |
| ½ cup creamy peanut butter | Flavor, binding | Almond butter, sunflower seed butter |
| 1 cup brown sugar | Sweetness, moisture | Coconut sugar, ¾ cup honey |
| ½ cup granulated sugar | Sweetness, structure | Organic cane sugar, monk fruit sweetener |
| 2 eggs | Binding, structure | 2 flax eggs (2 Tbsp ground flaxseed + 6 Tbsp water) |
| 2 tsp vanilla extract | Flavor | Almond extract, maple extract |
| 1½ cups Reese’s Pieces | Flavor, texture | M&Ms, chocolate chips, peanut butter chips |
Equipment Needed
– 9×13 inch baking pan
– Parchment paper
– Mixing bowls (large and medium)
– Electric mixer or stand mixer (optional but helpful)
– Rubber spatula
– Measuring cups and spoons
– Cooling rack
Step-by-Step Instructions

1. Preheat and prepare: Set your oven to 350°F (175°C). Line your 9×13 inch baking pan with parchment paper, leaving some overhang on the sides for easy removal later.
2. Mix dry ingredients: In a medium bowl, whisk together the flour, baking soda, and salt until well combined.
3. Cream wet ingredients: In a large bowl, beat the melted butter, peanut butter, brown sugar, and granulated sugar until smooth and well combined, about 2 minutes.
4. Add eggs and vanilla: Beat in the eggs one at a time, then stir in the vanilla extract until fully incorporated.
5. Combine wet and dry: Gradually add the dry ingredient mixture to the wet ingredients, stirring until just combined. Don’t overmix – this can make your Irresistible Reese’s Pieces Cookie Bars tough.
6. Add the star ingredient: Fold in 1¼ cups of the Reese’s Pieces, saving the remaining ¼ cup for topping.
7. Transfer and top: Spread the batter evenly into your prepared baking pan. Sprinkle the remaining Reese’s Pieces Cookies candy over the top, gently pressing them into the batter.
8. Bake: Place in the preheated oven and bake for 25-30 minutes, or until the edges are golden brown and a toothpick inserted into the center comes out with a few moist crumbs.
9. Cool completely: Allow the bars to cool in the pan for about 15 minutes, then use the parchment paper overhang to lift them out onto a cooling rack. Let them cool completely before cutting.
10. Slice and serve: Cut into 24 bars (or your preferred size) and enjoy!
Troubleshooting & Pro Tips
– Bars too dry? You likely overbaked them. Next time, check a few minutes before the suggested baking time. Remember, they’ll continue cooking slightly as they cool.
– Want extra peanut butter flavor? Add a drizzle of melted peanut butter over the top after baking but while still warm.
– Reese’s Pieces melting too much? Freeze them for 30 minutes before adding to the batter.
– For cleaner cuts: Use a warm knife (run under hot water and wipe dry) and clean between cuts.
– Perfect texture tip: Slightly underbaking these bars (while ensuring the center isn’t raw) will give you that coveted chewy texture.
Storage & Make-Ahead Tips
– Counter storage: Store in an airtight container at room temperature for up to 4 days.
– Refrigerator: Keep fresh for up to a week.
– Freezer: Wrap individual bars in plastic wrap, then place in a freezer bag for up to 3 months. Thaw at room temperature for about an hour before eating.
– Make ahead dough: The cookie dough can be prepared and refrigerated for up to 2 days before baking. Let it come to room temperature for about 30 minutes before spreading in the pan.
Conclusion
These Irresistible Reese’s Pieces Cookie Bars combine the best of two worlds – the convenience of bar cookies with the incredible flavor of Reese’s Pieces Cookies. The chewy, peanut buttery base packed with candy-coated pieces creates a dessert that disappears quickly at any gathering. Whether you’re making them for a bake sale, family dessert, or just to satisfy your own sweet tooth, these bars are sure to become a regular in your baking rotation!

FAQ
Can I make these gluten-free?
Yes! Simply substitute the all-purpose flour with a 1:1 gluten-free flour blend. The rest of the recipe remains the same.
How can I make these bars less sweet?
Reduce both sugars by ¼ cup each and consider using dark chocolate chips in place of some of the Reese’s Pieces.
Can I add chocolate chips to these bars?
Absolutely! Replace half of the Reese’s Pieces with semi-sweet or milk chocolate chips for even more chocolate goodness.
Why did my bars turn out cakey instead of chewy?
You might have used too much flour (measure by spooning into measuring cups, not scooping) or overmixed the batter. Also, make sure not to overbake.
Can I double this recipe?
Yes, but you’ll need to use two 9×13 pans rather than one larger pan to ensure even baking.
Follow me on Pinterest for more Irresistible Reese’s Pieces Cookie Bars. If you enjoy these bars, you might also love my Home Made Reese Cups recipe that offers another delicious way to enjoy this classic flavor combination!