With whipped heavy cream flavored with sweetened condensed milk and lime juice, these key lime mousse desserts are like the classic pie made in half the time.

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Straight on side view of three glasses filled with key lime mousse and topped with graham cracker crumble, surrounded by sliced limes, graham crackers, and spoons.

About Key Lime Mousse

If you’re a fan of key lime pie, you’re going to love this key lime mousse.

It’s like all the best parts of the classic pie – from the creamy and sweetly tart lime filling to the delicious graham cracker crust – all made in a fraction of the time and served in easy, eat-on-the-go glasses.

What’s in key lime mousse?

  • Heavy whipping cream, vanilla, and sweetened condensed milk – For creating the cream with a sweet flavor and thick texture.
  • Lime juice – Because you can’t have key lime without limes!
  • Green food coloring – Totally optional, but helps gives this dessert the visual cue of lime flavor.
  • Butter and graham cracker crumbs – To create the crunchy graham cracker topping, like a pseudo pie crust.
Top down view of glasses filled with key lime mousse, showing off the graham cracker crumble.

How many limes do you need?

This recipe calls for about 1/3 cup lime juice. Squeezing three medium limes should give you enough juice to work with (roughly two tablespoons of juice per lime.)

You can also use storebought lime juice for this recipe.

Can you make this in advance?

Certainly! These mousse desserts can be stored in the refrigerator for up to 24 hours before serving. However, I would recommend waiting to add the graham cracker topping until just before serving; that way it won’t get soggy.

How long is key lime mousse good for?

Once prepared, key lime mousse can be stored in the refrigerator for up to two days.

Close up side view of a single glass filled with key lime mousse, showing off the green color and golden graham cracker crumble.

Can you freeze key lime mousse?

Yes, you totally can!

You can store any leftovers in a sealed container or freezer bag for up to one month.

Notes & tips for key lime mousse

  • Green food coloring is used to give this dessert a lime-like hue, but it’s totally optional. Feel free to use as much (or as little) food coloring as you’d like.
  • If you don’t want to buy special graham cracker crumbs you can crumble standard graham crackers instead. I like to put them in a Ziploc bag and tap them a few times with a rolling pin or meat tenderizer until I get the consistency I need.
  • Salted butter is used in the crumbled topping to help counter the tartness of the lime juice. If you decide to not make the crumbled topping, I’d recommend adding a pinch of salt to the mousse itself.
  • For this recipe, I highly recommend using a stand mixer or a hand mixer. This isn’t a recipe you can make by hand with a whisk.
Spoon holding up a mixture of graham cracker crumble and key lime mousse with sliced limes and graham crackers in the distance.

More desserts with lemon and lime

How to make key lime mousse

This next part is only a photo tutorial of the recipe steps. If you’re looking for the full recipe measurements and instructions, scroll down to Recipe Details.

Step 1 – In a small bowl, mix together the graham cracker crumbs and melted butter, then set the bowl aside.

Step 2 – Whip the heavy whipping cream and vanilla extract until stiff peaks form. Turn off the mixer and gently fold in the sweetened condensed milk, lime juice, and green food coloring.

Step 3 – Add the key lime mousse to glasses or bowls and top with the graham cracker crumble.

Step 4 – Serve and enjoy!

Recipe Details

Straight on side view of three glasses filled with key lime mousse and topped with graham cracker crumble, surrounded by sliced limes, graham crackers, and spoons.
5 from 2 votes

Key Lime Mousse

15 mins prep
699 kcal
Yields: 4 servings
With whipped heavy cream flavored with sweetened condensed milk and lime juice, these key lime mousse desserts are like the classic pie made in half the time.

Ingredients 

Instructions

  • In a small bowl, add graham cracker crumbs and melted butter, then stir until all ingredients are damp and lightly clumping. Set bowl aside.
    3/4 cup graham cracker crumbs, 3 tablespoons salted butter
  • Using a stand mixer (or hand mixer + large bowl), add in chilled heavy cream and vanilla extract and beat on high until stiff peaks form, about 5-7 minutes.
    1 1/2 cups heavy whipping cream, 1 teaspoon vanilla extract
  • Remove bowl from mixer. Add sweetened condensed milk, lime juice, and green food coloring. Use a spatula to gently fold the ingredients together until food coloring is fully incorporated.
    1 cup sweetened condensed milk, 1/4 teaspoon green food coloring, 1/3 cup lime juice
  • Divide key lime mixture between four glasses. Top each glass with crumbled graham cracker mixture.
  • Serve immediately.

Nutrition

Serving: 1serving | Calories: 699kcal | Carbohydrates: 58g | Protein: 10g | Fat: 49g | Saturated Fat: 30g | Polyunsaturated Fat: 2g | Monounsaturated Fat: 13g | Trans Fat: 1g | Cholesterol: 149mg | Sodium: 293mg | Potassium: 424mg | Fiber: 1g | Sugar: 48g | Vitamin A: 1789IU | Vitamin C: 9mg | Calcium: 294mg | Iron: 1mg

I do my best to provide nutrition information, but please keep in mind that I’m not a certified nutritionist. Any nutritional information discussed or disclosed in this post should only be seen as my best amateur estimates of the correct values.

Author: Chrisy