These are the perfect lemon bars with a buttery shortbread base and a sweet and tangy lemon layer. The bright lemon flavor tastes like sunshine – making these perfect for spring and summer. They only require 7 simple ingredients and set beautifully.
These lemon bars are a classic treat that I think every baker should have in their recipe box. The bright lemon flavor reminds me of spring, but they’re perfect to make all year long since lemons are easily available. The start with buttery shortbread base. Then the lemon layer on top is the perfect balance of sweet and tangy without being too sour or sugary.
The Best Lemon Bar Recipe
After many recipe tests and taste tests – I found some lemon bars far too sweet, while others lacked enough lemon flavor. Another issue was that often the lemon layer wouldn’t set properly. But this recipe is perfect:
- The shortbread base is thick and buttery to balance out the sweetness
- The lemon flavor is tangy and sweet – but not sour
- The bars set beautifully for easy slicing
- There are no complicated recipe steps.
You’ll start by making the base. You’ll whisk together flour, sugar, corn starch (AKA corn flour) and a little salt. Then stir in melted butter. The dough will be thick. Then you’ll press the dough into the bottom of your lined pan and pop it in the oven to bake for about 20 minutes. The corn starch helps to keep the base soft, and the salt is needed to balance out the flavor of the bars.
As the base is baking, you can make the lemon layer. It’s made by simply whisking together eggs, sugar, corn starch and freshly squeezed lemon juice. When the base is done baking, you’ll remove it from the oven and gently prick the top with your fork. Don’t go all the way down to the bottom – just enough for the tines of the fork to gently pierce the very top of the shortbread. Then pour the lemon liquid over top, and pop the bars back in the oven for about 25 minutes.
A Note About Corn Starch: Corn starch is used to thicken the lemon layer and help it set properly. Some recipes use flour in the lemon layer instead. However, since corn starch has double the thickening power of flour – you can use less with better results. Do not leave the corn starch out!
A Note About Fresh Lemon Juice: This recipe calls for 1 cup of freshly squeezed lemon juice. 1 small lemon typically has about 3 tablespoons of lemon juice, whereas a large lemon may have up to ¼ cup (4 tablespoons). Therefore, I recommend buying about 5-6 small lemons or 4-5 medium/large lemons.
After the bars are baked and cooled, you can sprinkle a little powdered sugar on top. They’re also delicious with a dollop of whipped cream
Baking Tips & Tricks
- Use freshly squeezed lemon juice – not lemon juice from the bottle. Lemon juice from a bottle is far too sour for baking.
- Don’t forget to prick the top of the base layer with a fork after it bakes. This helps the lemon layer “stick” to the base, so it doesn’t seep around the edges of the base and go underneath.
- When the bars are done baking, the lemon layer should look set on top (if there are little air bubbles, that’s ok) and if you give the pan a nudge it shouldn’t wiggle. It will need to bake for about 25 minutes (in addition to the base baking on its own).
- Make sure to cool the bars fully. Let them cool at room temperature for about 1 hour, then pop the pan in the fridge for 2-3 hours before slicing. This allows the lemon layer to firm up.
More Lemon Recipes to Love:
- 9x13 inch (23 x 33 cm) baking pan*
- 2 ¼ cup all-purpose flour
- ½ cup granulated sugar
- 1 tablespoons corn starch
- ¼ teaspoon salt
- 1 cup unsalted butter melted
- 2 cups granulated sugar
- ⅓ cup corn starch
- 6 large eggs
- 1 cup lemon juice* freshly squeezed
- Preheat the oven to 325F (160C) degrees. Line a 9x13 inch pan with parchment paper, leaving an overhang around the edges.
- In a large bowl whisk together the flour, sugar, corn starch and salt.
- Stir in the melted butter. The dough will be thick.
- Press the dough into the bottom of the lined pan and create a small lip around the edges.
- Bake in the preheated oven for 20 -25 minutes, or until the base looks set and is just started to look golden around the sides. Make the lemon layer as the base is baking. Remove from the oven (and keep the oven turned on).
- Whisk together the sugar and cornstarch to remove any lumps.
- Whisk in the eggs, followed by the freshly squeezed lemon juice.
- When the base is done baking, remove it from the oven. Gently prick the very top of the shortbread with a fork (just go deep enough to prick the surface).
- Pour the lemon filling over top of the base and bake in the preheated oven (still at 325F) for 20-25 minutes, or until the top looks set and no longer wobbles like a liquid if you gently nudge the pan.
- Remove from the oven. Cool the bars in the pan at room temperature for about 1 hour, then pop the pan in the fridge to chill for at least 2 hours.
- When ready to slice, remove the bars from the fridge. Lift them out of the pan by using parchment paper overhang from the horizontal sides of the pan.
- Place on a cutting board and slice using a sharp knife. Optionally, sprinkle with powdered sugar.
- This recipe can be halved and made in an 8x8 inch pan. The bake time will be about 20 minutes for the base, and about 20 minutes for the lemon layer.
- Store bars in an airtight container in the fridge for up to 5 days. Bars can be wrapped tightly and frozen for up to 2 months in a freezer container. Thaw in the fridge.
- Make sure to use freshly squeezed lemon juice - do not use lemon juice from the bottle because it is too sour. You'll need about 5-6 small lemons or 4-5 large lemons for 1 cup of lemon juice.
- Nutrition information is an estimate only and based on 1 bar, assuming the pan is sliced into 18 equal pieces.