Springtime means bright, happy flavors. And whether you’re looking for a dessert for Easter, Mother’s Day, or any celebration, this low carb Blackberry Lime Tart fits the bill! With a crunchy pistachio crust, this keto dessert is bursting with all the best flavors of spring!
Low Carb Blackberry Lime Tart
This tart uses a combination of almond flour and pistachios to create a crust that has a little crunch to it, with flavors that complement the blackberry and lime.
For the filling we’re layering lime curd and blackberry curd. Then we top it all off with whipped cream and garnish with fresh blackberries and more chopped pistachios.
This is a slightly more complicated recipe. I’ll walk you through all the steps and give you my tips and tricks to give you the confidence you need. But if you like, you can jump to the recipe instead.
To make the crust, I pulsed whole, shelled pistachios with almond flour and my low carb sweetener in a food processor until the pistachios were finely chopped.
Don’t go too far, as you’ll start to release the oils from the nuts and your texture will get all funky. And not in the good way.
As I mentioned, I used my own low carb sweetener blend, but you could also use Sukrin Icing or Swerve Confectioners here if you prefer.
Once your pistachios are fine, turn your food processor on, and while running, add melted butter.
Press this firmly into a 9″ pan. I used a springform pan here, but you can also use a tart pan.
If you’re using a springform pan, press the crust halfway up the sides. If you’re using a tart pan, you can bring the crust all the way up.
Bake this at 350°F (175C°) for 7-10 minutes or until it’s just becoming golden on the bottom.
If you find that parts of it have puffed up as it’s cooked, use the bottom of a measuring cup to press it back down carefully while it’s still hot.
Allow to cool, then chill in the freezer while you make the lime curd.
For the lime curd, you need lime juice, lime zest, sweetener, eggs, and butter.
Note: If you’ve stumbled upon this recipe and you’re NOT following a low carb diet, you can substitute sugar 1:1 in this entire recipe.
To make the curd, whisk together the eggs and the sweetener. You’ll need to whisk very well so the eggs are completely homogeneous.
Note: This makes a lime curd that is on the tart side. I like it as is, but if you’re sensitive to it, or have a more intense sweet tooth, you can increase the sweetener by 1/4-1/2 cup.
In a saucepan, heat the lime juice with the lime zest just until it comes to a simmer.
Now we must temper the eggs. While whisking the eggs vigorously, add the hot lime juice in a thin stream. You can use a ladle for this, but I poured it back into the glass measuring cup and poured from there and it worked very well.
After that, return the mixture to the saucepan. Cook it slowly, stirring constantly with a wooden spoon, over medium-low heat.
Make sure you have everything you need for the next steps ready to go because once you start cooking this, you cannot walk away or get distracted. Do not stop stirring at any point.
It will do very little in terms of thickening for several minutes, and then it will thicken rapidly. You need to be watching because if you let it get too hot the eggs will scramble.
Once it gets thick, turn the heat off and add the butter one tablespoon at a time.
Once the butter is added, strain the mixture through a sieve. This is an important step for anything thickened with egg like this, as it’s not uncommon to get a few small flecks of cooked egg. You don’t want those in your curd.
Straining will also remove most of the lime zest. It’s already done its job flavoring the curd more intensely and getting it out makes for a smoother texture.
Spread it into the chilled crust, and place in the refrigerator while you make the blackberry curd.
Making the blackberry curd is essentially the same as making the lime curd, except that we first have to extract the seeds from the blackberries.
To do this, we put one pint of blackberries in a small saucepan with a squeeze of lemon juice.
Then we cook this down until the blackberries are very soft, then strain it through a sieve, pressing them very well to get as much juice and pulp out of them as possible. You should have about 1/2 cup of blackberry juice/pulp when you’re done.
The method for making the curd is exactly like the lime curd. Beat the egg with the sweetener, heat the blackberries, temper the eggs, then stir constantly over low heat until thick.
Because we’re making a smaller amount of blackberry curd than lemon curd, you’ll need to watch even more carefully because it will cook faster.
Once it’s thick, stir in the butter as before.
Strain the blackberry curd, then spread it evenly over the lime curd. An offset spatula works best for this.
Chill in the fridge for at least 30 minutes.
Right before serving, add the garnishes.
I highly recommend one of these cream whippers (I adore mine!) but you can also whip the cream by hand or with an electric mixer.
Isn’t it just gorgeous?
You need a slice in your life, my friends.
I recommend cutting this into 12 slices if you want to keep it at a more reasonable carb count. At 12 slices, each slice is 4.9g net carbs. If you decide you need a larger slice, 1/8th of the tart comes out to 7.3g net carbs. I did not include the garnishes in my calculations.
If you want to dazzle your guests with a stunning dessert that also hits all the right flavor notes, make this up right away, friends.
Your taste buds will thank you.
- 3/4 cup fresh lime juice
- zest of one lime
- 1 cup low carb sweetener
- 4 eggs
- 6 Tbsp butter, cut into pieces
- 1 pint (6 oz) blackberries
- squeeze of lemon juice
- 1 egg
- 1/4 cup low carb sweetener
- 2 Tbsp butter, cut into pieces
- whipped cream
- fresh whole blackberries
- chopped pistachios
- Preheat oven to 350F (175C).
- Prepare Crust: In a food processor, pulse pistachios, almond flour, and sweetener until pistachios are finely chopped. While running the food processor, add melted butter and mix thoroughly.
- Press crust mixture firmly into a 9" springform or tart pan.
- Bake for 7-10 minutes or until the bottom just begins to brown slightly.
- Allow to cool and then chill in the freezer while you prepare lime curd.
- Prepare Lime Curd: Heat lime juice and lime zest in a small saucepan over medium-low heat until simmering.
- While lime juice is heating, whisk eggs and sweetener together until very well mixed.
- Temper the eggs: whisk the hot lime juice in a slow steady stream into the egg mixture, stirring vigorously. Once all the lime juice is added, return the mixture to the saucepan.
- Stirring constantly with a wooden spoon, heat lime mixture for several minutes or until thickened to a gel-like consistency.
- Remove from heat, and stir in butter one tablespoon at a time.
- Strain lime curd through a sieve, then pour evenly over chilled crust. Place in refrigerator while preparing the blackberry curd.
- Prepare Blackberry Curd: Heat blackberries and lemon juice in a small saucepan until blackberries are very soft.
- Strain blackberries through a sieve, pressing fruit firmly through the sieve to get as much pulp through as possible. You should have about 1/2 cup blackberry pulp.
- Return strained blackberries to saucepan and heat to a simmer.
- While heating, whisk egg and sweetener together well.
- Temper the eggs: whisk hot blackberry juice in a slow steady stream into the egg mixture, stirring vigorously. Once the blackberry juice is added, return mixture to the saucepan.
- Stirring constantly with a wooden spoon, heat blackberry mixture for several minutes or until thickened to a gel-like consistency.
- Remove from heat and stir in butter one tablespoon at a time.
- Strain blackberry curd through a sieve, then spread evenly over lime curd.
- Chill in the refrigerator for at least 30 minutes.
- Right before serving, garnish with whipped cream, fresh blackberries, and chopped pistachios, if desired.
To Make Ahead:
Crust can be made ahead and stored, covered, in the refrigerator for up to 3 days.
Lime and blackberry curds can also be made ahead and stored in airtight containers for up to 3 days. It may take a bit more effort to spread cold curd evenly in the crust but should still work.
For best results, the tart should be assembled the same day it is served, although it may be assembled (without garnishes) the day before. Just be aware the crust may soften.
Garnishes should be added just before serving.
Amount Per Serving: Calories: 231Total Fat: 20.6gSaturated Fat: 7.4gSodium: 56mgCarbohydrates: 7.5gNet Carbohydrates: 4.9gFiber: 2.6gSugar: 2.9gProtein: 6.7g