Lemon Bars
Buttery shortbread base with tangy lemon filling, dusted with sugar for picnics and showers.
Updated: Oct 7, 2026
Why you'll like it
- Ready in about 55 min.
- Serves 16 — easy to halve or double.
- Easy level — everyday equipment only.
- Storage, freezing and reheating covered below.
Lemon Bars takes about 55 min and serves 16. Lemon bars are a bright USA dessert for spring showers, summer picnics, and cookie trays, combining buttery shortbread with tangy lemon custard.
Helpful guides
Instructions
Preheat the oven to 350°F and line a 9 by 13-inch pan with parchment. Beat softened butter with powdered sugar until smooth, then mix in 2 cups flour until crumbly. Press evenly into the pan with a flat cup.
Even thickness prevents thin spots that overbrown before the center sets.
Bake crust at 350°F for 18 minutes until lightly golden at edges. Keep the oven on. A prebaked crust stays crisp under the wet filling and slices cleanly.
Cool 5 minutes while mixing filling so the hot crust is ready to receive custard without delay or sogginess.
Whisk eggs, granulated sugar, lemon juice, zest, 0.25 cup flour, and baking powder until smooth with minimal foam. Strain if needed to remove zest clumps or chalazae. Pour over the warm crust.
Gentle whisking limits bubbles that would leave pinholes on the set lemon surface.
Bake at 350°F for 20 to 25 minutes until center barely jiggles and edges look set. The filling firms as it cools. Avoid browning the top; pale yellow with slight puff indicates doneness.
Overbaking causes rubbery texture and dulls fresh lemon flavor in the finished bars.
Cool completely on a wire rack for 1 hour, then refrigerate at least 2 hours at or below 40°F before cutting. Cold filling cuts neatly without dragging. Lift out with parchment, dust with powdered sugar, and cut into 16 squares with a sharp dry knife wiped clean.
Serve chilled or at cool room temperature. Keep dusted sugar light to avoid masking lemon tang. Return uneaten bars to refrigeration promptly.
Thorough chilling sets the custard layer so squares hold shape on platters during summer serving and transport to events.
Troubleshooting — fixes, not repeats
- If filling is runny, it was underbaked or cut warm. Bake until only the center jiggles slightly at 350°F, then chill 2 hours. Verify oven heat with a thermometer. Cutting early prevents starch and egg from setting fully into clean layers.
- If crust is soggy, it was not prebaked long enough. Bake 18 minutes until edges turn light gold before adding filling. Pour filling onto warm, not cooled, crust and return promptly to the oven to seal the base against moisture absorption.
- If top has bubbles, eggs were overwhisked. Whisk gently by hand, tap the pan once before baking, and avoid blender mixing. Strain filling to remove foam. Small bubbles can be hidden with powdered sugar but indicate excess air incorporation.
- If bars taste flat, lemon juice was insufficient or old. Use fresh lemons yielding 0.66 cup juice plus zest. Bottled juice varies in strength. Add zest for aroma without extra liquid, and measure sugar level to balance tartness accurately.
Make it your way
- Add 0.5 cup shredded coconut to the crust for texture, or replace 0.25 cup lemon juice with lime juice for lime bars.
- For berry lemon bars, scatter 1 cup fresh raspberries over the crust before pouring filling and bake 2 minutes longer at 350°F for set centers.
Storage & reheating
Cool leftovers within 2 hours, then refrigerate in a covered container and use within 3 to 4 days. Reheat only the portion you will eat until steaming hot throughout — poultry and reheated rice should reach 165°F (74°C).
Freeze undusted bars up to 3 months with parchment between layers.
Thaw overnight in the refrigerator, then dust with sugar before serving.
FAQ
Can I use bottled lemon juice?
Fresh juice is preferred for bright flavor, but bottled works in the same 0.66 cup amount. Add full zest only with fresh lemons. Bottled juice may taste slightly cooked, so increase zest or add 1 teaspoon fresh juice if available for aroma.
Why did my powdered sugar disappear?
Sugar melts into moisture on the bars over time. Dust just before serving rather than before storage. For longer holding, use a light second dusting at serving time. Refrigerate undusted bars and add sugar cold for better adherence.
Can I halve the recipe?
Yes. Halve all ingredients and bake in an 8-inch square pan at 350°F. Bake crust 15 minutes and filling 18 minutes. The thinner batch still yields 9 bars. Keep the same cooling and chilling times for clean slicing and firm texture.