Super creamy and rich, this keto peanut butter fudge recipe is the ultimate low carb and sugar-free treat for peanut butter lovers. It’s so easy to make, with only a few basic ingredients. Only 3g carbs per serving!
I can’t get this easy keto peanut butter fudge out of my mind! I updated the recipe recently and now it’s even better and easier than ever. I gave half of it away to my next door neighbour and I regret that now. Deeply.
At least it’s so easy to make, I can whip up a new batch any old time. And I will, believe me.
I have a number of sugar-free fudge recipes but most of them are chocolate based, like my keto rocky road fudge, or my dairy free keto chocolate fudge. They are wonderful and easy to make, but peanut butter makes a welcome change from all the chocolate.
Simplifying Keto Peanut Butter Fudge
I have to admit that sometimes I have a tendency to make things more complicated than they need to be. And this recipe is a perfect example.
Back when I first made it in 2017, I was attempting to make “old fashioned style” peanut butter fudge. I was trying to avoid the all-too-common low carb trick of adding cream cheese to get a more fudge-like consistency, because I do not enjoy the flavor of cream cheese in my fudge.
Making old fashioned fudge is a much more laborious process wherein you boil milk, sugar, and butter together until they reach the soft ball stage of candy making. Then you add the peanut butter and powdered sugar and beat the mixture for several minutes as it cools and thickens. You have to watch it carefully because it can go from almost liquid to too thick in moments.
It’s not a simple process and it relies on ridiculous amounts of sugar (at least 2 cups) to create the right consistency.
My first iteration of this keto peanut butter fudge mimicked that process, and used 1 ½ cups of sweetener. But keto sweeteners aren’t the same as sugar and don’t produce the same consistency. So I found myself adding some peanut flour to help it set properly. It was good, but more complicated than it needed to be.
Then it hit me that I was already sitting on the perfect peanut butter fudge recipe and had been for years and year. My Keto Peanut Butter Brownies, which I first created in 2013, had a delicious fudge-like topping. Why not simply make a bigger version of that?
A healthier fudge recipe with collagen protein
But never one to leave well enough alone, I still modified this recipe a little and added some keto collagen peptides. I don’t like overly sweet desserts anymore and using some collagen powder allowed me to reduce the powdered sweetener and still end up with an amazing creamy fudge.
Many keto dieters use collagen on a daily basis, for its myriad health benefits. It’s said to be very good for hair, skin, and joint health. It’s also a great source of healthy proteins.
I use the Perfect Keto Salted Caramel Collagen in my mid-morning cappuccino almost every day. It’s so good and makes for extra frothy coffee drinks. I cannot recommend it enough.
For this recipe, however, I used the plain unflavoured collagen, as I wanted the peanut butter to shine through. If you would prefer not to use collagen at all, you can add an additional ¼ cup to ⅓ cup powdered sweetener.
FYI that Perfect Keto offers all of my readers 15% off with code ALLDAY15
Tips for making Keto Peanut Butter Fudge
This keto fudge recipe is so simple and whips up in about 10 minutes. Here are my best tips for getting it right:
Line your loaf pan
This is a requirement if you want to get your fudge out in nice pieces. You can use waxed paper or parchment paper. Really press it into the corners and have overhanging edges so you can lift the whole batch of fudge out easily before cutting.
Use creamy peanut butter
There are a number of good all natural peanut butters on the market now that are nice and creamy. The creamier the peanut butter, the creamier your fudge will be.
If your peanut butter that has a lot of oil at the top, try to get as little of the oil into the mix as possible, as it can throw off the consistency and make the fudge too soft. A no-stir peanut butter is definitely a better option.
Salted or unsalted butter?
I personally use salted butter because I enjoy it in my sweets and think it brings out flavor. But some people are very sensitive to salt and if you’re one of them, you may want to use unsalted butter.
The powdered sweetener
A powdered sweetener is key to avoiding a gritty texture. Do keep in mind that I only tested this with Swerve and can’t say that it will work that well with other sweeteners. Some may make the mixture too soft and it won’t set properly. Check out my guide on keto sweeteners here for more details.
Collagen powder for consistency
Add collagen powder allows you to reduce the sweetener while still getting a wonderful creamy fudge texture. But if you can’t get any or you prefer not to use it, you can add an additional ¼ cup of powdered sweetener and achieve the same result.
How to store Keto Peanut Butter Fudge
I personally like this fudge best at room temperature and as long as your ingredients are fresh, it can last for up to 4 days in a covered container.
If it will be around longer than that, it’s best to store in the fridge and it should last for several weeks. Store it in a sealed container to avoid the fudge taking on the flavors of other refrigerated items.
Ready to make some easy keto peanut butter fudge? I think you will love it!
Try these other keto peanut butter recipes!
- Keto Peanut Butter Mousse
- Keto Peanut Butter Cookies
- Keto Peanut Butter Mug Cake
- Easy Keto Peanut Butter Cups
- Keto Peanut Butter Granola
- Keto Peanut Butter Chocolate Chip Skillet Cookie
Keto Peanut Butter Fudge
Ingredients
- 1 cup unsweetened creamy peanut butter (add a pinch of salt if it's unsalted)
- ½ cup butter
- ½ teaspoon vanilla extract
- ¾ cup powdered Swerve Sweetener
- ⅓ cup collagen peptides (see notes)
Instructions
- Line a loaf pan (8×4 inch or 5×9 inch) with waxed paper.
- In a medium saucepan over low heat, combine the peanut butter and butter. Stir until melted, then stir in the vanilla extract.
- Whisk in the sweetener and collagen until well combined and smooth. Pour the mixture into the prepared pan and refrigerate until set, about 1 hour.
- Lift the waxed paper out by the edges and cut the fudge into 15 pieces.
Jude says
Very easy to make and great treat that’s sweet.
RenaeMychelle says
my ingredients separated like a idk how to describe it but it’s weird looking. Should I whip it with a beater or immersion blender?. I think it’s either because I didn’t use creamy pb or I heated it too much
Carolyn says
Yes, see if you can get it to emulsify again by blending.
Mare Haugen says
Hey Carolyn, how I wish you were my neighbor. I am so impressed with all your recipes and read 99 percent of your recipes…. umm… maybe 95%. I need Lasik surgery and have a hard time seeing… good thing I learned to type while I still had good vision.
Am hoping, once I get my surgery and start feeling human again, I can read recipes and bake, even fry or roast something, anything. It’s been quite awhile. Unfortunately, my other half likes to make non-keto food and unfortunately, I love to eat so have failed to lose even ounces I think. No need to reply… I’m just trying to type again.
Carolyn says
If you were my neighbor, I would definitely cook and bake for you! 🙂 Good luck on your surgery.
Todd Flister says
is this mixable/bake-able with keto brownies?
Carolyn says
https://alldayidreamaboutfood.com/keto-peanut-butter-brownies/
Cherie says
Oh my goodness! I just made this and sooooo yummy….just licking the spatula! Can’t wait for the finished product. Thanks for feeding my addiction 🥰
Bluej says
Could I use whey protein powder instead of collagen? There’s always some ingredient I don’t have on hand. Thanks!
Carolyn says
I wouldn’t suggest it, to be honest. It’s likely to become gritty or not dissolve well. You can follow my instructions for skipping the collagen…
Judy Karg says
Made this last night and love it! After heating mixing, seemed too sweet and a little grainy. After a night in refrigerator tasted smooth and delicious. Please keep your fantastic recipes coming, appreciate all your hard work!
Samantha says
could u make this just chocolate fudge
Carolyn says
Please search “fudge” on my website and you will find my recipe for basic keto fudge.
Michele Maramarco says
thank-you for the recipe, very Easy,great snack,delicious.
Julie says
Super easy to make, but not a strong enough PB taste for me, with the sweetness overwhelming the PB. I make the filling for the Keto PB Easter Eggs, chocolate free, stuffing the dough into silicone candy molds which pops out beautifully after freezing. https://alldayidreamaboutfood.com/peanut-butter-eggs-low-carb-and-gluten-free/#recipe That recipe has much more PB taste and we eat that like fudge. Perhaps the peanut flour improves the PB taste, and it is less overwhelmingly sweet. I simplified the process of this recipe by gently microwaving the butter and PB rather than heating on a stove. Also used a silicone loaf pan without any wax paper or greasing, and it worked beautifully, as silicone products always do for me with LC baking. Your recipes are always appreciated!
Lutrecia says
I have not been able to print the recipes from your page for a while… I can print from other pages, just wondering what the problem is on this site…Thank you
Donna Yates says
I’ve been traveling in my motorhome for the past 3 months. I try to stick to simple recipes due to storage and space constraints. I made this recipe today but I only had almond butter. That being said, I could have eaten the entire recipe! Simply delicious!!
Christy says
I am so glad you posted this! I am allergic to peanuts, and was wondering if almond butter would work. Thank you! This page is awesome and my go to source for all keto foods.
Angela says
Hi, I used to make this fudge all the time and love it! Even make it as gifts. However, I just made a batch with the ‘new’ powdered swerve and this time the end results was a bit chalky and had some whitish spots all over the top after it cooled in the fridge. Before cutting it after an hour it looked fine with no white spots and was more creamy. This never happened before and the only thing that was different was the new swerve…..has anyone else noticed anything like this? I remember when I was stirring the mixture after I added the sweetener, it seemed like the swerve was just not dissolving all the way like it did before, and I stirred and stirred what seemed like forever. When poured it in the pan, it never really completely smoothed out as it always had before. Taste is still great but I miss it being more smooth and moist.
Carolyn says
That’s good to know… I have not tried this recipe with the new Swerve.
angela says
OK, I will see if I can order the original powdered swerve from amazon and try again.
Lori says
I made old fashioned peanut butter fudge for a church function and made this recipe for myself. My husband, who usually hates my sugar free version of anything, could not tell the difference. I refuse to make it again because I ate the whole batch in 2 days! It was so good I couldn’t stop eating it.
Carolyn says
Thanks so much! I have to save it for when I NEED to share it. 😉
Suzanne says
Hi Carolyn, my version ended up dry and crumbly after the addition of collagen and powdered sweetener and I wanted to ask if you might have any thoughts. I used 1/2 cup butter and 8 oz of Kroger natural peanut butter which contained only peanuts and salt and I poured off a small amount of extra oil on top. I used metric measurements for the sweetener and collagen. I used a powdered monk fruit/erythritol blend and for 3/4 cup I used 90 g (as this conversion seemed more appropriate for powdered sweetener) and 50 g for the 1/3 cup of collagen peptides (Ancient Nutrition Multi-collagen). My butter and peanut butter step looked like yours in the video, but after adding in the sweetener and collagen, my mixture was very dry and paste-like. I added some water (I know butter or coconut oil would have been better but water was fast) to be able to stir and spread into the loaf pan. I thought the color of my mixture was darker and that maybe I overheated the PB/butter, but then watching your video, my mixture looked the same as yours and I used very low heat. So I am a bit stumped and thought I would reach out if you had any thoughts. Love your site!
Carolyn says
Well that sounds disappointing. It really seems like it didn’t have enough oil so I think removing the extra oil could have contributed to the problem. But what other ingredients, if any, does your sweetener and your collagen have? If they have some additives, that also could be part of it.
Randi vicente says
I’m addicted. It’s absolutely delicious!
Elaine Cole says
I made this recipe again but with pecan butter and chocolate. It was wonderful! Thanks Carolyn!
Pete S says
Amazing. Great for a PB fix. Almost too sweet, but maybe since I haven’t had anything sweet for 3 months it may seem.a but extreme.
Billie Coleman says
Do you use the peanut butter flavored collagen or unflavored?
Carolyn says
I just used unflavored but you could certainly do the peanut butter.
Anthony says
I have the same Costco peanut butter only the oil is already mixed in. Does that matter?
Carolyn says
Should be fine!