Keto Iced Peanut Butter Bars: Low-Carb Dessert Recipe

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There’s something oddly comforting about the smell of peanut butter melting with butter — it’s like the aroma of a school cafeteria on treat day, except this time it’s keto. These Keto Iced Peanut Butter Bars take you straight back to those childhood squares of peanut-buttery goodness, but without the sugar crash that used to follow.

Soft, dense, and perfectly sweet with a creamy peanut butter icing, they’re the kind of low-carb dessert that feels indulgent but fits neatly into your keto goals. Whether you’re prepping snacks for the week or looking for something crowd-pleasing to share, these bars are quick, easy, and dangerously moreish.

Ingredients for Keto Iced Peanut Butter Bars

For the Bars

• ½ cup unsalted butter
• ¾ cup smooth peanut butter (no sugar added)
• 1 cup low-carb brown sweetener (monk fruit or erythritol blend)
• ½ teaspoon salt
• ½ tablespoon vanilla extract
• 2 large eggs
• 1 cup fine-blanched almond flour

For the Icing

• ¼ cup smooth peanut butter
• ½ cup low-carb powdered sweetener
• 4 tablespoons unsweetened almond milk
• ½ teaspoon vanilla extract

Pro tip: Choose a peanut butter with only peanuts and salt for the best keto-friendly result. Avoid “no-stir” brands that include added sugars or palm oil.

How to Make Keto Iced Peanut Butter Bars

1. Preheat & Prep:
   Preheat your oven to 350°F (180°C). Line or grease a 9×9-inch baking pan.
2. Melt Butter & Peanut Butter:
   In a small saucepan, melt butter and ¾ cup peanut butter over medium heat. Stir until smooth, then remove from heat and let cool slightly.
3. Combine Dry Ingredients:
   In a large bowl, mix sweetener, salt, and almond flour until evenly blended and lump-free.
4. Add Wet Ingredients:
   Whisk in vanilla and eggs, then pour in the melted butter-peanut butter mixture. Stir until you have a thick, cohesive batter.
5. Bake the Bars:
   Spread the batter evenly in the prepared pan. Bake for 20–25 minutes, or until the center is set and the edges are golden.
6. Prepare the Icing:
   While the bars bake, melt ¼ cup peanut butter in a small saucepan over low heat. Add almond milk and vanilla extract, stirring until smooth. Remove from heat, whisk in powdered sweetener, and adjust thickness with a splash more almond milk if needed.
7. Ice While Warm:
   Once baked, let the bars cool until warm (not hot). Pour the icing evenly over the top and spread with a spatula. Let it set for a few minutes before slicing into 12 squares.

Tips & Tricks for Perfect Peanut Butter Bars

• Ice While Warm: Icing spreads best when the bars are just warm enough to help it glide smoothly.
• Texture Check: Don’t overbake — the bars should stay soft and slightly fudgy in the center.
• Sweetness Control: Adjust sweetener to taste; monk fruit blends are milder, while erythritol adds more “bite.”
• Serving Idea: These pair perfectly with cold brew coffee or keto hot chocolate.

Substitutions & Variations

• Nut-Free Version: Swap peanut butter for sunflower seed butter or almond butter (check for unsweetened).
• Dairy-Free Option: Replace butter with coconut oil or vegan butter.
• Crunch Factor: Add a handful of chopped peanuts or sugar-free chocolate chips into the batter before baking.
• Flavor Twists: Mix a pinch of cinnamon or espresso powder into the icing for a deeper flavor.

Frequently Asked Questions

Can I freeze keto peanut butter bars?

Yes. Once fully cooled, freeze them in an airtight container with parchment between layers. Thaw overnight in the fridge before serving.

Can I make these with crunchy peanut butter?

Absolutely — it adds texture. Just note that the icing spreads more smoothly with creamy peanut butter.

How long do they last in the fridge?

Stored in a covered container, they’ll keep well for up to 5 days refrigerated.

Nutrition Information (Per Bar)

All nutritional data are estimates based on the ingredients used.

There’s something beautifully simple about a dessert that delivers both nostalgia and nourishment. These Keto Iced Peanut Butter Bars are soft, sweet, and just a little bit indulgent proof that comfort food doesn’t need sugar to feel like a treat.

If you make them, let yourself enjoy that first bite slowly that smooth frosting, that tender crumb and maybe, just maybe, you’ll hear the echo of a cafeteria bell somewhere in the background.

Try them this week, share them with someone who misses “the old days,” . After all, good things deserve to be shared.

Keto Iced Peanut Butter Bars (Low-Carb Dessert Recipe)

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Prep Time 6 minutes mins

Cook Time 25 minutes mins

Total Time 31 minutes mins

Course Dessert

Cuisine American

Servings 12 bars

Calories 275 kcal

Ingredients

  

For the Bars

• ½ cup unsalted butter
• ¾ cup smooth peanut butter (no sugar added)
• 1 cup low-carb brown sweetener (monk fruit or erythritol blend)
• ½ tsp salt
• ½ tbsp vanilla extract
• 2 large eggs
• 1 cup fine-blanched almond flour

For the Icing

• ¼ cup smooth peanut butter
• ½ cup low-carb powdered sweetener
• 4 tbsp unsweetened almond milk
• ½ tsp vanilla extract

Instructions

 

• Preheat & Prep:

  Preheat your oven to 350°F (180°C). Line or grease a 9×9-inch baking pan.
• Melt Butter & Peanut Butter:

  In a small saucepan, melt butter and ¾ cup peanut butter over medium heat. Stir until smooth, then remove from heat and let cool slightly.
• Combine Dry Ingredients:

  In a large bowl, mix sweetener, salt, and almond flour until evenly blended and lump-free.
• Add Wet Ingredients:

  Whisk in vanilla and eggs, then pour in the melted butter-peanut butter mixture. Stir until you have a thick, cohesive batter.
• Bake the Bars:

  Spread the batter evenly in the prepared pan. Bake for 20–25 minutes, or until the center is set and the edges are golden.
• Prepare the Icing:

  While the bars bake, melt ¼ cup peanut butter in a small saucepan over low heat. Add almond milk and vanilla extract, stirring until smooth. Remove from heat, whisk in powdered sweetener, and adjust thickness with a splash more almond milk if needed.
• Ice While Warm:

  Once baked, let the bars cool until warm (not hot). Pour the icing evenly over the top and spread with a spatula. Let it set for a few minutes before slicing into 12 squares.

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