Sugarless Key Lime Pie Recipe: Tangy Low-Sugar Dessert

This sugar-free key lime pie is an easy, no-bake dessert that requires no eggs. It’s a low‑carb treat featuring a sweet almond “graham cracker” crust and a bright, zesty lime custard filling.

This recipe uses simple, familiar ingredients—except for the key limes, which give the pie its distinctive aroma and tartness.

The Difference Between Key Limes and Regular Limes

Key limes are smaller and more aromatic than common limes, with a slightly floral note and sharper acidity. They can be harder to find—try specialty grocery stores or Mexican markets. If you can’t source them, regular limes are an acceptable substitute, though the flavor will be milder.

Because key limes are small, you’ll need more fruit to reach the required juice. In my experience one pound of key limes yielded about ½ cup of juice, so it’s helpful to have extras on hand.

How to Store Key Limes

Store key limes at cool room temperature rather than in the refrigerator; chilling can speed up decay. They generally don’t keep as long as standard limes, so plan to use them fairly quickly after purchase.

What Type of Sweetener to Use

Monk fruit sweetener is a good zero‑calorie, zero‑carb option that measures 1:1 like table sugar, making swaps simple. If you prefer maple syrup, reduce the quantity—use ½ cup maple syrup in place of ¾ cup sweetener, or ⅓ cup for a ½ cup sweetener substitution. If you use stevia or another concentrated sweetener, follow your usual conversion guidelines.

Gelatin

Unflavored gelatin provides structure and thickens the filling so it sets without baking. Warm (but don’t boil) the lime juice and dissolve the gelatin in it—too much heat can prevent the mixture from setting properly. Use an unflavored gelatin powder and avoid sweetened gelatin products that contain added sugar or artificial sweeteners.

How to Make Sugar Free Key Lime Pie

Summary of the process:

1. Warm the lime juice briefly, then stir in the gelatin until fully dissolved.
2. Beat softened cream cheese with sweetener, lime zest, and Greek yogurt until smooth.
3. Mix in the lime/gelatin mixture, taste and adjust sweetness or zest as desired.
4. Pour the filling into the prepared crust and chill until set.

How Does the Pie Taste?

Traditional key lime pie often uses eggs and sweetened condensed milk to create a silky, balanced custard. This version replaces those with cream cheese and full‑fat Greek yogurt (or sour cream) plus sweetener to achieve a creamy texture without eggs. Because there are no eggs, you can easily adjust the balance of sweet and tart—taste as you go.

For a bold, tart pie: use ½ cup key lime juice, 1 tablespoon zest, and ½ cup sweetener. For a sweeter, milder pie: use ½ cup juice, ½ tablespoon zest, and ¾ cup sweetener. Always taste the filling before transferring it to the crust and make small adjustments as needed.

Crust: Homemade or Store‑Bought

This recipe uses a simple no‑bake, low‑carb crust made from toasted blanched almond flour for a graham‑cracker-like flavor. You can substitute a store‑bought graham cracker crust if you prefer.

1. Toast 2 cups blanched almond flour in a dry nonstick skillet over medium‑high heat for 2–4 minutes until golden and fragrant—this step adds the graham cracker flavor.
2. Combine the toasted almond flour with cinnamon, sweetener, salt, and melted butter in a 9.5‑inch pie plate.
3. Press the mixture evenly into the bottom and up the sides to form the crust.

Chilling the Pie Is Important

Chill the pie for at least 2–3 hours to ensure the filling sets firmly; longer chilling improves texture and stability. Full‑fat yogurt or sour cream gives a firmer result—low‑fat versions can produce a wobblier filling. For a quicker firming, freeze briefly (about 1–1½ hours), then let the pie warm slightly before slicing.

How to Store the Pie

Keep the pie tightly covered in the refrigerator for up to 4 days.

Freezer Tips

Wrap the pie tightly in plastic wrap and foil and freeze for 1–2 months. Thaw overnight in the fridge, then bring to room temperature for an hour before serving if desired.

More Healthy Pie and Sugar‑Free Dessert Ideas

If you enjoy this recipe, other options to explore include sugar‑free apple pie, healthy peach cobbler, keto pumpkin pie, or a no‑bake peanut butter pie. There are several sugar‑free dessert recipes that use similar low‑carb techniques and sweeteners.

Sugar Free Key Lime Pie

Author: Brandi Crawford

This sugar‑free key lime pie is a simple, no‑bake dessert with a zesty lime custard and a buttery almond flour crust.

Recipe Details

• Prep Time: 25 mins
• Cook Time: 5 mins
• Chill: 2 hrs
• Total Time: 2 hrs 30 mins
• Servings: 10 slices
• Calories (per slice): 284 kcal

Equipment

• 9–10 inch pie plate
• Mixing bowl
• Hand mixer or stand mixer
• Skillet (nonstick or cast iron) for toasting almond flour

Ingredients

Graham Cracker Crust

• 2 cups blanched almond flour
• 1 teaspoon cinnamon
• ½ cup zero‑calorie sweetener
• ¼ teaspoon salt
• ½ cup (1 stick) unsalted butter, melted

Key Lime Pie Filling

• ½ cup fresh key lime juice (about 1 lb key limes)
• 6 oz cream cheese, softened
• 1 cup plain full‑fat Greek yogurt (or sour cream)
• ¾ cup zero‑calorie sweetener (adjust to taste)
• 1½ teaspoons unflavored gelatin
• ½ tablespoon key lime zest (adjust to taste)

Optional Garnishes

• Whipped cream
• Additional lime zest
• Thin lime slices

Instructions

Crust

1. Toast almond flour in a dry nonstick skillet over medium‑high heat for 2–4 minutes until golden and fragrant. This step builds the graham‑cracker flavor.
2. Transfer toasted almond flour to a 9.5‑inch pie plate. Add cinnamon, sweetener, and salt; stir to combine.
3. Gradually add the melted butter and mix until the mixture holds together.
4. Press the crust evenly into the bottom and up the sides of the pie plate. Set aside.

Filling

1. Warm the key lime juice briefly in the microwave for 30–45 seconds—warm, not boiling. Stir in the unflavored gelatin until fully dissolved; this may take a few minutes.
2. In a large bowl or stand mixer, beat the softened cream cheese with the sweetener, lime zest, and Greek yogurt until smooth.
3. Slowly add the lime/gelatin mixture to the cream cheese mixture and blend until fully combined. Taste and adjust sweetener or zest as needed.
4. Pour the filling into the prepared crust and smooth the top.
5. Chill for at least 2–3 hours until set. For quicker firming, freeze for about 1–1½ hours, then let rest at room temperature 10 minutes before slicing.

Notes

• A 9–10 inch pie yields about 10 standard slices; adjust macros accordingly if you slice differently.
• Key limes are more aromatic and tart than standard limes; substitute regular limes if needed.
• To make zesting easier, zest before juicing. Keep one standard lime on hand for zest if key limes are difficult to zest.
• If the filling doesn’t set, the gelatin may not have been fully dissolved into the warm lime juice.
• Powdered sweeteners can produce a smoother crust texture in no‑bake recipes, but granular sweeteners will also work.
• Do not use bottled lime juice—fresh juice makes a noticeable difference in flavor.
• Coconut oil can replace butter in the crust in equal amounts.
• Optional: add 1 teaspoon vanilla extract for a subtle vanilla note.

Nutrition

Per slice (approximate): 284 kcal, 4 g carbohydrates, 8 g protein, 26 g fat. These values are estimates and may vary based on exact ingredients and portion sizes.