Keto Peanut Butter Fudge
Ultra creamy, three-ingredient Keto Peanut Butter Fudge that is only 2 net carbs per slice!

My favorite Keto Peanut Butter Fudge has only three ingredients and takes just a few minutes to make. This ultra creamy fudge has a caramel base that adds a rich flavor you will love! Once you make the keto caramel, just stir in peanut butter, freeze and top with a little sea salt for a decadent keto holiday dessert!
The ultra low carb count makes this fudge a great keto snack. This could also be called a keto fat bomb. A ketogenic diet is a low-carb, high fat diet. When on keto your primary energy source is fat, so people often add fat bombs to their diet to meet their quota or add a little boost. Fat bombs can be sweet or savory they must be low in carbs and high in fat.

Ingredients in Keto Peanut Butter Fudge
This low carb peanut butter fudge recipe has three ingredients:
- butter
- swerve brown sugar sweetener
- peanut butter
You will find this recipe has the best flavor and results with butter and the brown sugar swerve. If you swap those for granular Swerve it will lack the same rich caramel flavor that the brown sugar version provides.
However it will still be sweet and delicious, just not quite the same. You definitely can switch the peanut butter for a different nut butter, just make sure it is a low carb/no sugar added version to keep your carbs at bay.
Can You Have Peanut Butter on Keto?
Yes! For this recipe, any peanut butter will work so long as it’s not one of the high-carb versions that contain extra honey or sweeteners.
How to Make Keto Peanut Butter Fudge
This keto-friendly peanut butter fudge couldn’t be simpler to make! Here are the basic steps:
- In a sauce pan, melt the butter and add brown sugar.
- Stir continuously until sugar dissolves and it begins to simmer and a thick brown caramel begins to form.
- When the sauce is thickened and looks like caramel remove from heat and stir in the peanut butter until melted.
- Line a loaf pan with wax paper and carefully pour the fudge into the pan.
- Freeze until completely set.
- Peel the wax paper away from the fudge and slice.
- Top with sea salt as desired.
How to Store Keto Fudge
After slicing I find these store best in an air tight container in the freezer. Simply set them out one at a time for a few minutes to allow them to thaw. When thawed just a bit they melt in your mouth!

Tips for Making Low-Carb Peanut Butter Fudge
- For added flavor, add 1 teaspoon vanilla extract to the keto fudge.
- I like to slice the loaf of fudge into three long, skinny rows, then slice the long rows into 7 chunk-size pieces.
- If stored in the freezer, this keto-friendly peanut butter fudge will last up to 3 months.
More Great Desserts:
- Keto Cheesecake Brownies
- Pecan Turtles
- Keto Lemon Bars
- Cranberry White Chocolate Macadamia Nut Cookies
- Keto French Silk Pie
- Turtle Candy

Get the Recipe: Keto Peanut Butter Fudge
Ingredients
- 8 tablespoons butter, 1 stick
- 1/2 cup brown sugar swerve sweetener
- 1 cup peanut butter
- 1 teaspoon vanilla extract, optional
Instructions
- Heat a medium size sauce pan over medium heat. Melt butter, then add brown sugar. Stir continuously until sugar dissolves and it begins to simmer and a thick brown caramel begins to form. This usually takes 6-8 minutes for me. (see video below)
- When the sauce is thickened slightly and looks like caramel, remove from heat and stir in the peanut butter and vanilla extract (if using) until melted.
- Line a loaf pan with wax paper and carefully pour the fudge into the pan.
- Freeze 30 minutes or until completely set.
- Peel the wax paper away from the fudge and slice. (I slice the loaf into three long skinny rows, then slice the long rows into 7 chunk size pieces.)
- Top with sea salt as desired.
- Store in freezer.

Love it, I will also make variations with sugar free coffee flavours like Matteo or skinny syrups or add chocolate. Also made with crunchy all natural peanut butter and I love every variation so far!!!
Today I made this recipe, my first ever keto or sugar-free recipe. It turned out quite nice the first time around! Very much appreciate the recipe and the work that went into developing it.
I’ve been simmering and stirring for at least 25 minutes with no thickening. I’m doing a double batch. Now what? Expensive fail.
Oh my gosh! Why would you cook it 25 minutes?! I wrote that it took mine 6-8 minutes. Did you not watch the video? This is a straightforward recipe. Once the butter and sweetener have thickened slightly to create a caramel like sauce add the peanut butter and stir until smooth. Freeze and slice.
looks fabulous! I think I’ll add maple flavoring instead of the vanilla.
I can’t get the consistency correct with the Swerve and butter. First time I had the heat higher but it wouldn’t thicken up. Second time over lower heat and it was thicker but the fudge ended up grainy. This third time I kept on medium heat, I kept it there for a long time and it smells like I over cooked it. It never did thicken up. I just put them in the freezer but I don’t think they are going to turn out well. Any pointers on the heat? They taste great. Thank you.
Hi Bill, I just use medium heat in this recipe and it only requires a few minutes of cook time. Perhaps you can watch the recipe video and it may help.
Could I add keto cocoa powder? Do you think this would still work or would it be too dry to hold together? Also, when and how much would you maybe recommend adding?
Hi, I plan on making this for my family!! Question…where did you buy your enameled saucepan for this recipe?!? Is it Le Creuset?!? Thank you ?
Unsalted or salted butter! Thank you!
Lura, I’ve used both with excellent results, it is your preference.
These are by far the best keto dessert I’ve had so far! I’d make these every day if I could, lol.
About my tenth time of making this. We love it. I love how simple it is to make. I wish I had words to describe how it tastes when you just take a bite and it starts to melt a little in your mouth. Pure peanut butter delight! Thank you for sharing this!
Made this with Lakota Golden Monkfruit And my husband and I love it!! Thank you!