Keto Lemon Mousse

Why You’ll Love This Recipe

I love how quick and easy this mousse is to whip up. It’s a no-bake dessert that feels fancy but takes almost no effort. The combination of rich heavy cream with fresh lemon juice and zest gives it a balanced flavor—tart, sweet, and silky smooth. It’s also perfectly portioned for anyone following a low-carb or ketogenic lifestyle, so I can indulge without breaking my macros. Best of all, it feels like a treat but keeps me on track.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

1 cup heavy cream
¼ cup powdered erythritol (or preferred keto-friendly sweetener)
2 tablespoons lemon juice
1 tablespoon lemon zest
½ teaspoon vanilla extract
Optional: Extra lemon zest or fresh mint leaves for garnish

Directions

1. In a mixing bowl, I combine the heavy cream, powdered erythritol, lemon juice, lemon zest, and vanilla extract.

2. Using a hand mixer or a whisk, I beat the mixture on medium-high speed until it thickens and forms soft peaks. I make sure not to overbeat it—once it’s thick and smooth, I stop.

3. I spoon the mousse into individual ramekins or small serving glasses.

4. I cover them with plastic wrap and refrigerate for at least 2 hours so the mousse can firm up and the lemon flavor can really shine through.

5. Just before serving, I top each dish with a little extra lemon zest or a sprig of fresh mint to make it feel extra special.

Servings and timing

This recipe makes 4 servings and takes just 10 minutes of prep, plus at least 2 hours of chilling. It’s the perfect make-ahead dessert for dinner parties or an easy weeknight treat.

Variations

Sometimes I like to switch it up by using lime juice and zest instead of lemon for a tropical twist. I’ve also folded in a few mashed raspberries or strawberries for a fruity swirl. If I want to make it extra decadent, I layer the mousse with crushed keto cookies or a dollop of whipped cream. For a frozen variation, I freeze the mousse in silicone molds for a refreshing summer treat.

Storage/reheating

This mousse keeps well in the refrigerator for up to 3 days in covered containers. I never freeze it, as the texture can change, but it’s best enjoyed chilled straight from the fridge. I love making it the night before so it’s ready when I want a fuss-free dessert.

FAQs

Can I use bottled lemon juice instead of fresh?

Yes, I’ve used bottled lemon juice in a pinch, but I always prefer fresh lemon juice and zest for the best flavor and aroma. The zest really makes a difference.

Can I use a different sweetener?

Absolutely. I usually use powdered erythritol because it dissolves easily, but monk fruit, allulose, or a blend also works. I just adjust to taste.

How do I know when the mousse is done mixing?

I stop mixing when the cream forms soft peaks—when it holds its shape but still looks smooth and creamy. Overmixing can turn it into butter, so I keep a close eye on the texture.

Can I add gelatin to make it firmer?

If I want a firmer, more structured mousse, I sometimes dissolve ½ teaspoon of unflavored gelatin in warm lemon juice and let it cool slightly before adding it to the mixture. It’s optional but works well if I need it to hold up longer.

Is this mousse good for meal prep?

Yes! It’s perfect for meal prep. I portion it into jars or ramekins, cover tightly, and refrigerate. It stays fresh and delicious for a few days, and it’s a great way to have a keto dessert ready whenever I want one.

Conclusion

This Keto Lemon Mousse is the kind of dessert I keep coming back to—simple, elegant, and bursting with flavor. It’s light enough to enjoy after any meal but rich and creamy enough to feel indulgent. Whether I’m following a strict keto plan or just trying to cut back on sugar, this mousse gives me the sweet fix I want without the carbs I don’t.

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