Preheat a fan-forced oven to 180C / 350F (180C / 395F for no fan). Spray a 20cm / 8-inch square cake tin with oil spray and line with baking paper.
Make the biscuit crumb - Add the all-purpose flour, corn starch, powdered sugar, salt, and lemon zest to the bowl of a food processor. Blitz until well combined, about 30 seconds. Add the butter and blitz for about 30-40 seconds until you reach pea sized butter.
Bake - Pour into the cake tin and spread out. Press down firmly using our hands or a flat-bottomed glass/measuring cup. Bake for 8 minutes or until light and golden. While the crust is baking, make the filling.
Lemon Filing
Lower oven temperature - Lower your oven temperature to 150C / 300F (170C / 340F for no fan).
Make lemon filling - Add the lemon zest, caster sugar and flour to a large mixing bowl. Use a whisk to combine. Then add the eggs and lemon juice. Whisk until just combined. Take care not to overmix! We don’t want to over-aerate the filling.
Bake - As soon as the crust is baked, pour the filling on top. Bake for 22 minutes or until the middle is set and only has a slight jiggle. The top should barely be golden. Take care not to overbake or it will feel like eating rubber and won’t be perfectly gooey.
Cool down - Once baked, allow to cool at room temperature for 2 hours, then chill in the fridge for 4 hours to set. Dust with powdered sugar and then use a large knife to slice up.
For super clean slices - Run a large knife under hot water and dry. Make a slice. Wash under hot running water and dry again before the next slice. This is how to get nice sharp edges!
Lemons - wherever you buy your lemons, make sure you give them a good scrub under some warm water to rid them of that shiny wax coating they put on them at the store to make them look shiny. Nobody wants to eat that!StorageThese Lemon Bars can be stored in an airtight container for up to three days.BakingDon’t overbake your lemon bars or you’ll end up with a rubbery lemon layer instead of something that’s nice and gooey.Storage - Lemon Bars can be stored in an airtight container, in the fridge for up to four days.Nutrition - is an approximate and is based on per slice. This recipe makes 9 bars.A note on measurements - this recipe is offered in weight measurements. This is in an effort to offer the most accurate way to get the best results. Cup measurements simply aren’t accurate enough for a recipe that needs precision and cup sizes differ depending on where you are in the world. Here is where you can learn more about how to measure ingredients using digital kitchen scales!