When life hands you lemons (& limes & mint), riff on a classic lemon bar with Mint Lemon Lime Bars. They're sweet & tart with a hint of mint!
I have a High Tea tradition with my daughters.
I take them for tea on their birthdays, no matter the day or the distance. It’s our way of celebrating them on their special day.
On our very first tea date when she was 5 years old, my older daughter was served a lemon bar, and she was hooked. Now I make lemon bars (aka lemon squares) every so often when the mood strikes, and I like to get her opinion whenever possible.
She is a connoisseur after all.
Finding that I had lemons, and limes, and mint in the refrigerator, I riffed on a classic lemon bar recipe. Mint Lemon Lime Bars bars, anyone?
[Side Note: I updated this recipe in April, 2021 with a new type of crust, more flavor in the filling, and all new pictures. You're welcome!]
Adapting a classic recipe
For my Mint Lemon Lime Bar recipe, I replaced the requisite ½ cup lemon juice found in most lemon squares with a mixture of lemon and lime juice, plus their finely grated zest.
The shortbread base uses melted butter, so the dough mixes quickly.
Oh, and let's not forget the mint! That arrives in the form of mint sugar. More on that later.
I've got lemons...and limes...and mint...let's get to it, shall we?
How to make Mint Lemon Lime Bars
There are two main steps to these bars: making the shortbread, then making the lemon and lime curd filling. Let's dive in a little deeper.
Step 1: Make the shortbread base
The shortbread starts with melted butter that's been cooled to room temperature. If the butter is too warm, it may not mix well with the other ingredients and will separate out during baking.
After mixing in the flour, the shortbread dough will be soft and pliable.
Press the dough into a 9- by 9-inch baking pan with your fingers. I find that covering the top with plastic wrap helps to create a flatter surface.
Par-bake the shortbread just until the edges are lightly browned.
After the shortbread comes out of the oven, lightly prick it with a fork, but NOT all the way through. This step is optional, but it helps to seal the filling to the base.
Step 2: Make the lemon and lime curd filling
While the shortbread is in the oven, start to make the lemon lime curd filling.
Before we get to that, let's prep our mint and dry ingredients.
In order to get the mint chopped as finely as possible, use a food processor to mix it with the sugar. This has the added benefit of infusing the sugar with the mint oil.
Using powdered sugar in the filling gives the curd a creamy texture, and the small amount of cornstarch helps to firm things up. Sifting the flour with the powdered sugar helps to prevent lumps.
Lightly beat the eggs before adding the rest of the curd ingredients. You don't want a lot of air in there.
Pour the filling onto the warm, poked shortbread, tapping out the air on the counter before heading to the oven.
One trick I read about is using binder clips to keep the parchment paper away from the curd while it bakes. Just clip them to the sides of the pan and bake away!
Despite our best intentions, imperfections can occur. If you over-whip the eggs, trapped air will bubble up even if you tap them out before putting the pan in the oven. Cracks can appear in the surface of the bars when the curd is over-baked.
That's what happened in this pictured batch.
Like with cheesecake, you can turn off the oven a couple of minutes before the filling is entirely set and crack the oven door, allowing the filling to cool gradually before removing it to cool completely.
And of course, a generous dusting with powdered sugar can cover up the worst of it!
When you're ready to slice up the bars, have a jug of hot water and a towel nearby. Wiping off the knife between cuts gives you neater slices.
Add more powdered sugar just before serving to cover imperfections or disappearing topping. And no matter what they look like, these bars will taste fabulous!
The bars are best served chilled, and dusting them with the powdered sugar just before serving helps to keep it from melting away.
Questions asked and answered
Here are some questions that you might have...
Instead of using a food processor to grind the sugar and mint together, just finely chop the mint by hand (my chef instructors at school would call it “mint confetti”) and add it in with the rest of the filling ingredients.
Using freshly juiced fruit will give the brightest flavor, but you can use bottled juice in a pinch.
Yes! Any citrus juices can be used, in any combination. Just make sure there's the equivalent of ½ cup of juice in total. If you're using sweeter fruit, like oranges, you might want to reduce the sugar up to ¼ cup (but not much more as the sugar helps the curd texture). And don't forget to add the zest to up the flavor punch!
Despite tapping out the air bubbles, they can still show up after baking. It happens when the eggs are over-whipped or the curd is over-baked. To prevent cracking, turn off the oven a couple of minutes before the filling is entirely set and crack the oven door, allowing it to cool gradually. If either of these things happen, a good sprinkling of powdered sugar will cover them up.
Citrus forward taste with a hint of mint
These Mint Lemon Lime bars are sweet and pleasantly tart. The mint peeks out on the backend as you go to take another bite. The lemon and lime curd is soft and creamy, and the shortbread holds everything together well.
My older daughter, the connoisseur, loves them!
Treat yourself, your family, and your friends to a bright new way of enjoying lemon bars.
Move over, lemon bars...there's a new flavor in town!
Slainté! L’chaim! Cheers!
Recipes using lemons
Want lemony goodness in your life? Try some of these citrus recipes!
Recipes with lemons...
Drinks featuring lemons...
The Best Mint Lemon Lime Bars
For the shortbread
- ½ cup unsalted butter, melted and cooled
- ¼ cup granulated sugar
- ¼ tsp kosher salt
- 1 cup all-purpose flour
For the filling
- 1 cup granulated sugar
- ½ cup fresh mint leaves, packed
- ¼ cup all-purpose flour
- 2 Tbsp powdered sugar, plus more for dusting, see Recipe Notes
- 4 large eggs
- 1 large egg yolk
- ⅓ cup lemon juice, freshly squeezed, from 2 lemons, see Recipe Notes
- 2 Tbsp lime juice, freshly squeezed, from 1 lime, see Recipe Notes
- 1 Tbsp zest, lemons and lime combined, see Recipe Notes
- ¼ tsp kosher salt
- Preheat oven to to 325°F. Lightly coat a 9- x 9-inch baking pan with baking spray or butter. Line the baking pan with two pieces of parchment paper placed perpendicular to each other, covering all four sides and leaving a 2-inch overhang. Set aside.
- Make the shortbread: In a medium bowl, mix the cooled melted butter, sugar, and salt. Add the flour and stir to combine.
- Transfer the shortbread dough into the prepared baking pan. Press the dough evenly into the pan. Refrigerate the dough for 15 minutes.
- Par-bake the shortbread for 18 to 22 minutes, or until the edges are lightly browned.
- Make the filling: While the shortbread is baking, put the sugar and mint leaves in a small food processor and pulse until they’re finely blended. In a separate small bowl, sift the flour and powdered sugar together.
- In a large mixing bowl, lightly beat the eggs until just combined. Add the mint sugar, flour mixture, lemon and lime juices and zest, and salt. Whisk until just combined.
- Remove the par-baked shortbread from the oven and pierce the top it lightly with a fork (don’t go all the way through). Pour the curd filling onto the warm crust. Tap the pan a couple of times on the counter to release the trapped air.
- Return the pan to the oven and bake for 18 to 20 minutes, or until the center is set and doesn’t jiggle when the pan is tapped. Turn off the oven a couple of minutes before the filling is entirely set and crack the oven door, allowing it to cool gradually.
- Remove from the oven and cool counter for 1 hour, then chill for 1 hour more. Using a fine-mesh strainer, generously dust the bars with powdered sugar, then use the parchment paper as a sling to transfer to a cutting board.
- Cut the slab into 16 squares. It’s best to dip the knife in hot water and wipe it dry between cuts to get neater squares.
- Dust with more powdered sugar, if desired, then serve and enjoy bright lemony-limey-mint goodness!