The Most Amazing Skinny Peanut Butter Swirl Brownies

Meet your new favorite low-fat, high-protein brownies! Gooey chocolate brownie meets creamy peanut butter swirls in this delicious classic dessert. Each brownie is 100 calories – so easy to make and seriously melt in your mouth good!

While these are very similar to both the 100-Calorie Black Bean Brownies and Fudgy Mint Brownies, there are a couple of things that are slightly different.

For one, I used applesauce instead of pumpkin. Not a huge difference, but still changes things up some. And then of course, this amazingly tasty peanut butter swirl! With just the right about creamy peanut butter goodness with brownie in each bite. What better combo than peanut butter and chocolate?! SO SO GOOD.

I still made them in a 9×9″ pan because I wanted them to be thicker over thinner. Thick, dense brownies all day! I seriously just can’t describe these. They are amazing and such a fun treat!

Why You’ll Love These Brownies:

  • Easy to make – just throw everything for the brownies in a food processor
  • Made from healthy ingredients so you can feel good about eating them
  • Only 100 calories a brownie!
  • And packed with fiber (3.6g) and protein (11g)
  • CHOCOLATE and PEANUT BUTTER, enough said.
  • Even better when chilled the next day

What You Need:

  • Cannellini or black beans – these make the brownies dense and you do not taste them at all!
  • Unsweetened applesauce
  • Sugar free pancake syrup – I use Walden Farm’s or Cary’s brand. You can always use pure maple syrup too.
  • Egg
  • Almond milk – or any milk of choice
  • Protein Powder – I used PEScience Chocolate Peanut Butter Cup. You can use any flavor though! If you use another brand, just make sure it is a whey + casein blend as well.
    For all Pescience products, you can use code “LaurenFitFoodie” to save 10%.
  • Cocoa Powder – I love Hershey’s dark
  • Oat flour – I love the texture the oat flour brings, but you can substitute with all-purpose, almond, or gluten-free flour too.
  • Reduced-calorie hot cocoa mix – may sound odd, but the level of chocolateness this mix brings cannot be matched! A good sub for this would be sugar-free chocolate jello pudding mix. If you are looking to keep artificial sweeteners down, Simply Delish brand is amazing! But I still highly recommend the cocoa mix!

What About The Peanut Butter Swirl?

To make the peanut butter swirl, all you need is peanut butter powder, protein powder and cold water! For peanut butter powder, I love PBfit. For protein powder, I would recommend a peanut butter or vanilla flavor over a chocolate one. I love using PEScience’s Peanut Butter Cookie protein powder.

Pour the peanut butter sauce over the brownie layer in a zig zag-like motion. This will make the “swirl” effect come together better. From there, use a toothpick or a knife to make circles in the batter. You want to swirl enough so that the peanut butter isn’t all in one spot, but not too much where you are mixing the brownie and peanut butter layer. Too much swirling will combine the colors of each, which is not what we want!

How To Store

For best results, keep stored in an airtight container in the fridge. They will keep up to 7 days.

They are even better the next day after being refrigerated overnight! The flavors come out more and they also form a more dense, gooey-like texture. I think they taste better cold and prefer eating them that way as well.

You can also freeze some to have in case of a chocolate emergency 😉
Just pre-cut, wrap each brownie in parchment paper or wax paper, then keep sealed in an airtight ziplock bag. They will keep frozen for up to 3 months.

As always, if you try, tag me on Instagram (@LaurenFitFoodie), because I love seeing your yummy recreations!

Yield: 12

Skinny Peanut Butter Swirl Brownies

Skinny Peanut Butter Swirl Brownies

Meet your new favorite low-fat, high-protein brownies! Gooey chocolate brownie meets creamy peanut butter swirls in this delicious classic dessert. Each brownie is 100 calories – so easy to make and seriously melt in your mouth good!

Prep Time 10 minutes
Cook Time 25 minutes
Total Time 35 minutes



  • 1 (15.5 ounce) can of cannellini beans or black beans, rinsed and drained (235g once drained)
  • 2 scoops chocolate or peanut butter flavored protein powder (64g) - I used PEScience Chocolate PB Cup 
  • 3 tbsp Hershey's cocoa powder (15g)
  • ½ cup oat flour (60g) 
  • 2 envelopes reduced-calorie hot chocolate mix (22g) 
  • ½ tsp baking powder
  • ¼ tsp baking soda
  • ½ cup unsweetened applesauce (113g) 
  • ¼ cup sugar-free pancake syrup (60g) 
  • 1 large egg
  • ¼ cup unsweetened vanilla almond milk (60 mL) 

PB Swirl

  • ⅓ scoop Pescience Peanut Butter Cookie protein powder (10g)
  • 4 tbsp peanut butter powder (32g) 
  • 3 tbsp cold water (45 mL)  **make sure to add slowly so you don't add too much!


  1. Preheat oven to 350 F. Spray a 9x9" baking dish with cooking spray.
  2. In a food processor, combine all the ingredients for the brownies and blend until smooth. Pour the batter into the baking dish and spread evenly across.
  3. In a separate bowl, combine the protein powder, peanut butter powder and water. Stir until combined.
  4. Drizzle the peanut butter cookie evenly across in a zig zag method. Use a toothpick to make circles in the batter and spread the peanut butter swirl across. Be careful not to swirl too much as to not combine the brownies and peanut butter.
  5. Bake for about 20 to 25 minutes. Be sure to watch carefully not to over-bake! Toothpick should come out still somewhat gooey. Brownies will continue to bake some in warm pan.
  6. Take out, and let cool. Enjoy warm or let sit in fridge overnight for even fudgier brownies! (10/10 would recommend eating chilled!)


MFP entry:

Lauren Fit Foodie Peanut Butter Swirl Brownies

Nutrition Information:



Serving Size:

1 brownie (58g)

Amount Per Serving: Calories: 106Total Fat: 1.7gSodium: 238mgCarbohydrates: 13gFiber: 3.6gSugar: 1.9gProtein: 10.5g

Did you make this recipe?

Please leave a comment on the blog or share a photo on Instagram and tag me @LaurenFitFoodie! 


  1. These Peanut butter brownies look so good. I am starting journey ok so I guess I have really been on this journey for years but, I am looking forward to trying these to give me options for sweet cravings and you have so many options to choose from

  2. These are SO GOOD! I’ve made them 3 weeks in a row! But I plug my own recipes in for myself into MFP and when I made this, to the T as written, it gives me 1.8F/17.6C/12.2P. Just an fyi!

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