Equipment
* optional
Ingredients
Shortbread Crust
- 115 g unsalted butter, melted and slightly cooled
- 40 g granulated sugar
- 125 g all-purpose flour
- 2 g salt
- 5 ml vanilla extract
Lemon Filling
- 200 g granulated sugar
- 15 g all-purpose flour
- 3 eggs, room temperature
- 10 g lemon zest, freshly grated
- 120 ml fresh lemon juice
Garnish
- 15 g powdered sugar
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 161 kcal
- Protein
- 2 g
- Carbohydrates
- 23 g
- Fat
- 7 g
- Fiber
- 0 g
- Sugar
- 16 g
- Sodium
- 63 mg
- Saturated Fat
- 4 g
- Monounsaturated Fat
- 2 g
- Polyunsaturated Fat
- 0 g
- Cholesterol
- 50 mg
- Potassium
- 34 mg
- Calcium
- 10 mg
- Iron
- 0.3 mg
- Magnesium
- 4 mg
- Phosphorus
- 30 mg
- Zinc
- 0.2 mg
- Vitamin A
- 64 mcg
- Vitamin C
- 4 mg
- Vitamin D
- 0.2 mcg
- Vitamin E
- 0.3 mg
- Vitamin K
- 1 mcg
- Vitamin B6
- 0.0 mg
- Vitamin B12
- 0.1 mcg
- Thiamin
- 0.02 mg
- Riboflavin
- 0.05 mg
- Niacin
- 0.1 mg
- Folate
- 8 mcg
- Water
- 17 g
- Alcohol
- 0 g
Sources: USDA FoodData Central
Method
Preheat the oven to 175°C (350°F). Line a 20x20cm baking pan with parchment paper, leaving an overhang on the sides to act as handles for easy removal later.
In a mixing bowl, combine the melted butter, granulated sugar, all-purpose flour, salt, and vanilla extract. Stir until the mixture is completely hydrated and forms a cohesive, soft dough.
Transfer the dough to the prepared baking pan. Using your hands or the back of a spoon, press the dough firmly and evenly across the bottom of the pan.
Bake the crust in the preheated 175°C (350°F) oven for 20 minutes, or until the edges are lightly golden brown. Keep the oven turned on once the crust is removed.
While the crust is baking, whisk together the granulated sugar and all-purpose flour for the filling in a clean mixing bowl to remove any flour lumps. Add the room temperature eggs, lemon zest, and fresh lemon juice. Whisk thoroughly until smooth and frothy.
Immediately pour the prepared lemon filling over the warm crust as soon as it comes out of the oven.
Carefully return the pan to the 175°C (350°F) oven and bake for an additional 20 to 25 minutes. The bars are done when the center is set and no longer jiggles when the pan is gently tapped.
Remove the pan from the oven and place it on a wire rack. Allow the squares to cool completely at room temperature for at least 2 hours.
Once entirely cool, use the parchment overhang to lift the bars out of the pan onto a cutting board. Dust generously with powdered sugar and slice into 16 even squares using a sharp chef knife.
Chef's Notes
- Using freshly squeezed lemon juice is non-negotiable for the brightest flavor. Bottled juice lacks the vibrant, fragrant essential oils found in fresh citrus.
- For the cleanest slices, transfer the completely cooled bars to the refrigerator for an hour to chill the filling firmly before cutting.
- Whisking the dry sugar and flour together before adding wet ingredients for the filling is a crucial step to prevent small lumps of unmixed flour from floating to the surface.
- Glass and metal baking pans conduct heat differently. If using a glass dish, you may need to add 3 to 5 extra minutes to your baking times.
Storage
Refrigerator: 1 week — Store in an airtight container or cover tightly with wrap.
Freezer: 3 months — Freeze completely cooled squares wrapped individually, before dusting with powdered sugar. Thaw overnight in the refrigerator.
Troubleshooting
Filling seeped under the crust and stuck to the pan
Cause: The crust was not pressed firmly enough into the corners, or the crust was allowed to cool completely before the liquid filling was added.
Fix: Cannot be fixed structurally, but carefully lifting with a flexible spatula will salvage the pieces. They will still taste delicious.
Prevention: Press the crust dough firmly against the edges of the pan and pour the filling over the crust while it is still hot from the oven to create an instant seal.
White foam layer baked onto the surface of the bars
Cause: Air bubbles trapped during the whisking process rose to the top during baking.
Fix: Cosmetic issue only; a generous dusting of powdered sugar will completely hide it.
Prevention: Whisk gently rather than vigorously, or let the filling rest for 5 minutes before pouring to allow bubbles to dissipate.
Cultural Context
Lemon bars became an American dessert staple in the mid-20th century, with the first widely printed recipe appearing in the Chicago Daily Tribune in 1962. They evolved from traditional shortbread and English lemon curd tarts into a distinctly simple, potluck-friendly traybake format beloved during spring gatherings and holidays like Easter.
