How to make classic lemon bars

Zest up afternoon tea with this classic lemon dessert recipe. Buttery shortbread base topped with smooth and citrusy lemon butter. So delicious! And eye-catching too, with its bright natural yellow colour - ideal for bake sales. Learn how to make butter bars and avoid these common mistakes.

Classic lemon bars with shortbread crust recipe

LEMON BUTTER FILLING

1 cup (215g) caster sugar
1 tablespoon finely grated lemon rind
½ cup (125ml) lemon juice
2 egg yolks
4 whole eggs
150g Western Star Chef’s Choice Butter, cold, cut into 1cm cubes
3 teaspoons cornflour

SHORTCRUST BASE

100g Western Star Chef’s Choice Butter, chopped, softened
1 teaspoon vanilla extract
¼ cup (55g) caster sugar
1 egg
⅓ cup (35g) desiccated coconut
¾ cup (115g) plain flour
Icing sugar mixture, to decorate

LEMON BUTTER FILLING

Combine eggs, sugar, rind and juice in a heatproof bowl over a saucepan of gently simmering water. Cook, whisking, for 3 minutes or until sugar has dissolved
Gradually add the butter, one or two cubes at a time, whisking continuously. Remove from heat. Whisk in cornflour. Set aside to cool slightly while making the base

SHORTCRUST BASE

Preheat the oven to 180°C/160°C (fan-forced) and grease a 20cm square cake tin. Line base and sides with baking paper, extending paper 2cm above pan edges
Beat butter, sugar and vanilla together with an electric mixer until light and fluffy. Beat in egg. Mixture will look curdled at this point
Add coconut and flour and beat on low speed until combined. Spoon into the base of the prepared pan and spread evenly with a spatula or back of a spoon. Bake for 15 minutes or until light golden. Remove from oven
Pour over warm lemon butter filling. Bake for 20-25 minutes or until set. Remove. Cool to room temperature, then refrigerate until firm
To serve, dust with icing sugar and slice into bars with a hot knife

Save the recipe to your myfoodbook cookbooks here: Lemon Butter Bars

Tips for making the lemon butter

When making the lemon butter, it's important to whisk eggs, sugar, lemon juice and rind in a bowl over a saucepan of simmering water for the right amount of time before adding the butter. Warming the mixture for 3-5 minutes is essential to let the sugar dissolve, and also to help the butter emulsify into the eggs (avoiding a split mixture).
When you're ready to add the chilled butter, add it only 2-3 cubes at a time, while whisking continuously over simmering water. The lemon butter will begin to thicken.
Remove bowl from the heat and whisk in cornflour. It will dissolve instantly in the hot egg mixture, thicken the curd and stabilize the egg emulsion. Cornflour will also help prevent the lemon butter from splitting when baked in the oven.

Common lemon butter bar mistakes

Why did my lemon butter split?

If you add the butter too fast, it can split your curd because the butter hasn’t had a chance to emulsify properly. Ensure your butter is cut into small cubes, is chilled and you only add a couple of cubes at a time while whisking continuously.  Your curd could also split if the mixture is too hot, make sure the bowl isn’t touching the water below. The water should be barely simmering, not boiling.

Why did my lemon bars split?

There are a couple of things that could cause your bars to split. Add the right amount of cornflour to the mixture, the cornflour helps to stabilise the lemon butter and too little could result in splitting. Don’t over-bake the lemon bars - this can cause cracks. Once out of the oven let them cool gradually and completely in the tin, then refrigerate.

Why are my lemon butter bars rubbery?

This can happen if you cook at too high a temperature or you overcook them. Double-check your oven temperature. The lemon bars are ready to take out of the oven when they’re still slightly jiggly in the centre. If there's no more jiggle, they may be overdone.

How do you fix runny lemon bars?

This recipe uses cornflour to thicken the curd and ensure your lemon bars never turn out runny. If your lemon bars don't set properly, they make not have been baked long enough. The filling should jiggle slightly in the centre when you remove it from the oven, but the edges should be set. If it's too jiggly, it won't set properly. You can try putting it back into the oven if the curd doesn't set, but there will be a risk of the curd splitting or cracking.

Why did my crust get soggy?

The crust can get soggy if the lemon curd is too hot when you pour it over the shortcrust base. It’s important to follow the recipe exactly, by making the curd first and letting it cool properly while making the base. The curd will thicken as it cools, so it will sit on top of the base instead of running underneath it.

Try these other baked treats

You can never have too many baking recipes. Below are more classic treats like shortbread, jam drops and butter cake.

GET THE RECIPE: 3 Ingredient Buttery Shortbread with Passionfruit Butter by Western Star

GET THE RECIPE: Buttermilk and Vanilla Bean Scones by Western Star