Go Back
Lemon Bars coated in powdered sugar
Print

Lemon Bars

Course Dessert
Prep Time 30 minutes
Cook Time 45 minutes
Cooling Time 1 hour
Total Time 2 hours 15 minutes

Equipment

  • 8"x8" (20cm) square baking dish (metal or glass)
  • Parchment paper (I like these pre-cut ones because they lay flat)
  • Food processor (or pastry blender)
  • Fork
  • Medium saucepan
  • Whisk
  • Silicone spatula
  • Microplane zester
  • Strainer
  • Wire rack

Ingredients

Ingredients for Shortbread Crust

  • 7 ½ tbsp (107g) unsalted butter, cold and cut in cubes
  • 4.5 tsp (10.5g) powdered sugar
  • 4.5 tsp (19g) granulated sugar
  • 1 cup + 2 Tbsp (136g) all-purpose flour
  • Small pinch salt

Ingredients for Lemon Bar Filling

  • 6 Tbsp (86g) unsalted butter, softened
  • 3 tsp (6g) lemon zest, finely grated (approximately 1 large lemon)
  • ½ cup (143g) lemon juice, freshly squeezed and strained
  • 6-8 large (140g) egg yolks
  • cup (300g) granulated sugar
  • Small pinch of salt
  • 3 Tbsp (27g) powdered sugar (for dusting)

Instructions

Preparation Steps

  • Preheat oven to 325°F/160°C and place the rack in the middle of the oven.
  • Prepare the baking dish with two pieces of overlapping parchment paper (or aluminum foil) with the paper extending a few inches past the edges of the pan to help remove the bars after cooking. If you skip this step, it will be difficult to remove them and cut them into neat squares.

Making the Shortbread Crust

  • In a food processor, add powdered sugar, granulated sugar, and butter. Pulse until the sugar is incorporated into the butter. You can also do this step using a pastry blender instead of a food processor.
  • Add flour and salt and pulse until incorporated. The dough will look crumbly (think coarse crumbs), but it should hold together when pinched.
  • Scrape the dough into the base of the prepared baking dish and use your fingers to press the dough into a flat and even layer.
  • Use a fork to dock the dough (i.e., prick holes in the dough) so air bubbles will not form in the shortbread crust while baking. Docking the dough will also help adhere the lemon curd filling to the crust.

Baking the Shortbread Crust

  • Bake the crust for 15 minutes. For even baking, rotate the pan halfway around continue baking for an additional 15 minutes (or until golden brown).
  • Remove the pan from the oven and leave it to rest while making the lemon curd.
  • Reduce the oven temperature to 300°F/150°C.

Making the Lemon Curd

  • Place lemon zest in the bottom of a medium bowl and set to the side.
  • Add butter, granulated sugar, and egg yolks to a medium saucepan and whisk to combine. This will be a thick mixture.
  • Whisk in the lemon juice and salt. It is likely the mixture will look curdled at this point. Don’t worry, it will smooth out while cooking.
  • Cook the lemon curd over medium-low heat until thickened. Stir the lemon curd constantly with a silicone spatula making sure to scrape the sides and bottom of the pan to avoid burning the mixture. It will take 10-15 minutes to cook the curd, but don’t be tempted to increase the cooking temperature to speed the process up. It’s very easy to overheat the curd. If it reaches boiling, it will cause the eggs to scramble, and the lemon curd will look curdled.
  • Cook the curd until it reaches nappe (i.e., when the curd coats the back of a spoon and maintains a line when a finger is drawn across the spoon instead of dripping down to fill in the line) or approximately 180°F/83°C. You can also tell it’s ready if you drop some of the curd back into the pot and it leaves a small pool or trail for a few seconds before sinking back into the curd.
  • Immediately pour the curd through a strainer and into the bowl with lemon zest. Don’t let the curd sit in the hot pot because it will continue to cook and will likely burn.
  • Stir the lemon zest into the lemon curd to incorporate it and then pour the hot curd on top of the baked shortbread.

Bake the Lemon Bars

  • Bake the Lemon Bars for 15 minutes or until the edges of the lemon curd are set. The middle should still be a little jiggly if you shake it.
  • Remove the bars from the oven and allow to cool completely in the pan.
  • Refrigerate the lemon bars (in the pan) for 30 minutes to an hour to ensure the lemon curd is firm enough to cut.

Cutting the Lemon Bars

  • Remove the lemon bars from the fridge and run a small, sharp knife around the outside edge of the pan to make sure the lemon bars are not stuck to the pan. Then, use the edges of the parchment paper to pull the bars out of the pan.
  • To get really neat squares, use the following tips:
    - Use a large chef’s knife to cut the width of the bars in one motion (i.e., no sawing motion).
    - Most glass pans are rounded on the sides. If your pan is rounded, cut the rounded edge off on each side to get straight and clean outside lines.
    - Use a ruler to measure even spacing for the bars. I cut 9 squares at about 2¼“ (6cm) each side.
    - Wipe off the knife between cuts. Lemon bars are sticky so there will be residue left on the knife between cuts, which will make the edges of the bars bumpy.
    - Immediately before serving, dust the tops of the bars with powdered sugar. The powdered sugar will dissolve as it sits.

Storing Lemon Bars

  • Store in an airtight container at room temperature for 3 days or in the fridge for up to 3 weeks.