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closer view of keto marshmallow fluff recipe

Low Carb Keto Marshmallows

Prep Time 25 minutes
Cook Time 6 hours
Total Time 6 hours 25 minutes
Servings 9 Marshmallows
Calories 19kcal


  • 1/2 Cup cold Water (for gelatin)
  • 3 - 3 1/2 Tablespoons Gelatin 3 for erythritol based sweeteners, 3 1/2 for allulose based sweeteners
  • 2/3 Cup Water (for the sweetener)
  • 2 Cups Swerve, Lakanto, or Trader Joe's Allulose granular (note 1)
  • Pinch Kosher Salt
  • 1 1/2 Teaspoons Vanilla Extract


  • Prep. We will need to work quickly while the marshmallows are hot, so prepare an 8x8 casserole (note 2) dish with parchment paper and grab your electric (or stand-up) mixer. Set aside.
  • Combine. Add 1/2 cup cold water to a large bowl. Sprinkle gelatin (3 tablespoons) on top and whisk until it dissolves. Set aside for 10 minutes.
  • Heat. Meanwhile, add 2/3 cup water, sweetener (2 cups), and a pinch of salt to a saucepan over medium-hgih heat. Whisk as you bring this combo to a boil, and continue to boil for 2 minutes.
  • Whisk. After 10 minutes, run the stand up or electric mixer in your bowl with the gelatin to break it into small clumps. With the mixer on, pour in the hot erythritol water, plus the vanilla extract (1 1/2 teaspoons). Make sure to transfer the erythritol water straight from a boil to the bowl (no resting time) -- we want to keep this combo as hot as possible, as once it starts to cool, it will set, which will lead to clumps in the marshmallows. Whisk (nonstop) on high for around 12 minutes. If using a hand mixer, move the mixer around continuously, you don't want the marshmallows to "set", and moving will prevent this. After 12 minutes, your marshmallows should be fluffy and will have doubled in size.
  • Shape. Pour marshmallow fluff into your prepared baking dish. Allow them to dry (uncovered) on the counter for 6 hours (note 3). Once firm, cut your marshmallows using a greased sharp knife (I rub melted butter along the edge of the knife with a paper towel). Store cut marshmallows in the fridge, and enjoy!


  • Sweetener - Lakanto, Swerve, or Trader Joe's Allulose. My preferred sweetener here is Trader Joe's Allulose, as allulose doesn't recrystallize when cool. If using Swerve or Lakanto, your marshmallows WILL have a gritty texture (this is just the erythritol recrystallizing. That said, allulose produces a softer marshmallow. You can add more gelatin to combat this (I suggest using 3 1/2 tablespoons).
  • Casserole dish size. If making large squares, use an 8x8 casserole dish. To cut shapes into your marshmallows (hot chocolate photo above), use a 9x13 casserole dish. Note that your marshmallows won't be as tall.
  • Setting the marshmallows - 6 hours at room temp is great if your kitchen is cool. I made these during summer (around 80F in my kitchen) and had to put them in the fridge for the last hour so they would fully set.


Calories: 19kcal | Total Carbohydrates: 22g | Protein: 4g | Fat: 1g | Sodium: 6mg | Fiber: 1g | Sugar: 1g | Net Carbs: 0g | Sugar Alcohol: 21g

Delicious recipe from Lindsey Hyland // www.thelittlepine.com