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–+ servings
Sourdough lemon bars recipe.

Sourdough Lemon Bars

Carmyn Suzor
Sourdough lemon bars are made with fresh lemon and sourdough discard for a sweet, tangy, irresistibly delicious treat. Easy to make and perfect for any occasion!
5 from 3 votes
Prep Time 15 minutes
Chill Time 6 hours
Cook Time 50 minutes
Servings 15 bars

Ingredients
 

Sourdough Shortbread Crust

  • 2¾ cups (330 g) all-purpose flour
  • 1 cup (120 g) powdered sugar
  • ½ teaspoon salt
  • ¼ cup (62 g) sourdough discard
  • 1 cup (226 g) melted unsalted butter
  • 1 teaspoon (5 g) vanilla extract

Lemon Filling

  • 3 cups (600 g) sugar
  • 8 eggs
  • ½ cup (60 g) all-purpose flour
  • 1 cup (240 g) fresh lemon juice + zest from the lemons about 5 large lemons, NOT bottled lemon juice

Instructions
 

  • Heat the oven to 350°F and line a 9x13 metal baking dish with parchment paper.
  • In a large mixing bowl, whisk together 2¾ cups all-purpose flour, 1 cup powdered sugar, and ½ teaspoon salt until fully combined. Add ¼ cup sourdough discard, 1 cup melted unsalted butter, and 1 teaspoon vanilla extract and mix together until the dough just comes together. Do not overwork the dough.
    Optional: For a long fermentation, cover the pan and refrigerate the uncooked dough for up to 48 hours. Remove the cover and bake straight from the fridge for 25 minutes.
    Sourdough shortbread crust dough in a bowl.
  • Transfer the dough to the baking dish and press it out to a flat even layer. Bake for 20-25 minutes or until the surface is a light golden color.
    Optional: For a long fermentation, cover the pan and refrigerate the uncooked dough for up to 48 hours. Remove the cover and bake straight from the fridge for 25 minutes.
    Sourdough shortbread crust dough pressed out in a baking dish.
  • In large bowl, beat 8 eggs with a whisk. Add 3 cups sugar, 1 cup fresh lemon juice + zest from the lemons, and ½ cup all-purpose flour and mix until smooth.
    Lemon filling for sourdough lemon bars in a bowl.
  • Pour the filling onto the warm crust, then carefully return the pan to the oven and bake for 25 minutes. The filling should wobble slightly but not appear wet on the surface.
    Lemon filling poured on top of sourdough shortbread crust in a baking pan.
  • Remove the pan from the oven and let the bars cool for 1 hour before refrigerating for at least 6 hours to fully set. Do not skip the cooling and refrigeration steps—allowing the lemon bars ample time to set is essential for the perfect texture.
    Baked sourdough lemon bars in a pan.
  • Before serving, dust the surface with powdered sugar and use a sharp, clean knife to cut into bars.
    Sourdough lemons bars topped with powdered sugar and lemon slices on a table.

Notes

Tips:

    • Fresh lemon juice is a MUST! Bottled or concentrated juice just doesn’t compare and will alter the flavor. Stick to fresh for the best taste.
    • Line the baking pan. The delicate filling makes parchment paper essential—it allows you to lift the bars out easily without breaking them.
    • Use a sharp, clean, slightly damp knife. Running a sharp knife under warm water before cutting (and re-dampening it after each slice) ensures clean, precise edges.
    • Don’t worry if the filling wobbles! A slight jiggle is normal when they come out of the oven. They’ll continue to set as they cool and firm up in the fridge.
    • Don't skip chilling in the fridge: Proper chilling is key to allow the lemon filling to set, achieving the perfect texture.

How to Store

Storage: Keep sourdough lemon bars in an airtight container in the fridge for up to one week.
Freezing: Wrap individual bars in plastic, layer with aluminum foil, and freeze for up to three months.

Nutrition

Serving: 1barCalories: 434kcalCarbohydrates: 71gProtein: 6gFat: 15gSugar: 48g