This Blueberry Key Lime pie is made using a premade graham cracker crust and frozen wild blueberries. Since the layers are added separately, you have the option of creating a blueberry swirl pie by simply stirring the blueberry topping into the key lime filling just before placing it in the oven. We’ve all seen swirled cheesecakes. I’m not sure why more bakers don’t create swirled key lime pies but I highly doubt I’m the first to come up with the idea.
This tangy key lime pie can easily be put together in 20 minutes. It uses a premade graham cracker crust, which is standard for key lime pie. If you have a few extra minutes and want to make your own graham cracker crust, visit my article Super Easy Graham Cracker Pie Crust. You can also use a refrigerated store-bought crust if you’re looking for a traditional flaky crust.
This recipes calls for only six ingredients excluding the crust. You’ll notice that I recommend frozen wild blueberries. The blueberries must be thawed and drained. Being from New England where wild blueberries grow abundantly on the side of the road and in fields, I’m always surprised when a recipe says you can use frozen berries without thawing them. Frozen blueberries release up to 20% more liquid than fresh berries. You can check out my article Key Tips For Making Blueberry Pie.
You’ll notice this recipe calls for cornstarch. Cornstarch is used to thicken the blueberry filling. If you’re not a big fan of cornstarch you can use any common pie thickener. The most common pie thickeners are flour, cornstarch, Clearjel and tapioca. Only cornstarch and flour would work as a thickener for this type of pie. If you don’t mind the blueberry topping being a bit runny due to the high liquid content, then by all means omit the cornstarch.
Blueberry key lime pie brings together two flavors that brighten each other in the best possible way. The key lime filling delivers that sharp, floral citrus zing, and the blueberries add a deep sweetness that softens the tartness without dulling it. When the two meet, the result is a layered flavor profile—tangy, sweet, creamy, and fruity—that feels refreshing and vibrant in every bite. The contrast makes the pie taste lively and satisfying, with each forkful offering a little burst of brightness wrapped in smooth, silky custard.
What You’ll Need To Make This Pie
Utensils & Tools
- Medium bowl
- Small bowl
- Wire whisk
- Spatula or spoon
- Measuring cup
- Set of measuring spoons
Key Ingredients
- Graham cracker crust
- Sweetened condensed milk
- Egg yolks
- Cornstarch
- Key lime juice or regular lime juice
- Frozen blueberries frozen thawed and drained
- Blueberry extract or flavoring (optional)
Blueberry Key Lime Pie Recipe
Utensils & Equipment
- 1 medium bowl
- 1 small bowl
- 1 wire whisk
- 1 spatula or spoon
- 1 measuring cup
- 1 set of measuring spoons
- 1 fork
Ingredients List
- 1 graham cracker crust
- 14 ounces sweetened condensed milk
- 4 egg yolks
- 1 Tbsp cornstarch
- 1/2 cup key lime juice or regular lime juice
- 12 ounces blueberries frozen thawed and drained
- 1/2 tsp blueberry extract or flavoring (optional)
Instructions
Preheat Oven
- Preheat the oven to 350℉.
Prepare The Bottom Filling
- In medium bowl whisk together the egg yolks until they are well blended.
- Whisk in the sweetened, condensed milk then add the key lime juice.
- Set the bowl aside to thicken while preparing the blueberry layer.
Prepare The Blueberries
- In a small bowl mix together the drained blueberries and cornstarch. The cornstarch is to thicken the blueberry topping. If you want the topping to be slightly runny then omit the cornstarch.
Assemble The Pie
- Pour the filling into the graham cracker crust.
- Next, scoop or pour the blueberry topping onto the key lime filling.
- PRO TIP: If you want a blueberry swirl pie, gently swirl the blueberries into the key lime filling.
Bake
- Bake at 350℉ for approximately 20 minutes. The center of the pie should be slightly jiggly and not fully set.
Cool
- Refrigerate for at least 2 hours.
Nutrition
Frequently Asked Questions
Can I use regular lime juice instead of key lime juice?
Yes, regular lime juice works perfectly fine in this recipe. Key limes have a slightly more floral and intense flavor, but standard Persian limes still create a deliciously tangy pie. Fresh squeezed juice gives the brightest flavor, although bottled lime juice can be used in a pinch.
Do I have to use frozen blueberries?
No. Fresh blueberries work just as well when they are in season. Frozen blueberries are convenient because they are available year-round and already soft enough to blend easily into the topping. If using frozen berries, thaw and drain them well before mixing them into the pie filling.
Why is my blueberry topping runny?
The blueberry layer can become runny if there is too much liquid in the berries. Cornstarch helps thicken the topping and gives the pie a cleaner slice when served. Be sure to drain thawed blueberries well before adding them to the recipe.
Can I make this pie ahead of time?
Absolutely. This pie is actually better when made ahead because the filling has time to fully chill and set. Preparing it the night before serving allows the lime flavor to deepen and gives the pie a firmer, creamier texture.
Can I make my own crust instead of using premade?
Yes. A homemade graham cracker crust works beautifully with the creamy lime filling and sweet blueberries. If you prefer a more traditional pie texture, a refrigerated flaky pie crust can also be used.
Storage & Serving
How To Store Blueberry Key Lime Pie
Store the pie covered in the refrigerator for up to 4 days. Because the filling contains egg yolks and sweetened condensed milk, it should always remain chilled when not being served. A pie container or loosely tented plastic wrap works best to protect the creamy surface from absorbing refrigerator odors.
Can You Freeze This Pie?
Yes. Blueberry Key Lime pie freezes surprisingly well. Wrap the cooled pie tightly in plastic wrap followed by aluminum foil and freeze for up to 2 months. Thaw overnight in the refrigerator before serving. The texture may soften slightly after freezing, but the flavor remains bright and refreshing.
Best Ways To Serve This Pie
This pie tastes best served cold straight from the refrigerator. For an extra bakery-style presentation, top each slice with whipped cream, fresh blueberries, thin lime slices, or a sprinkle of lime zest. The chilled creamy filling and tangy citrus flavor make it especially refreshing during warm weather months.
