Sourdough Chocolate Chip Cookie Bars

Sourdough Chocolate Chip Cookie Bars

These sourdough chocolate chip cookie bars are thick, soft, chewy, and packed with melty chocolate chips. They’re a great way to use up sourdough discard, and the discard adds a subtle tang that balances the sweetness and gives the bars a wonderfully rich flavor.

Ingredients

For the cookie bars

• 1 cup (226 g) unsalted butter, melted and slightly cooled
• 1 cup (200 g) packed light brown sugar
• ½ cup (100 g) granulated sugar
• ½ cup (120 g) active sourdough starter or sourdough discard, 100% hydration
• 2 large eggs
• 2 teaspoons vanilla extract
• 2½ cups (315 g) all-purpose flour
• 1 teaspoon baking soda
• ¾ teaspoon salt
• 1½ cups (255 g) semi-sweet or milk chocolate chips
• ½ cup (85 g) chocolate chunks, optional
• Flaky sea salt, optional, for topping

Instructions

1. Prepare the pan.
   Preheat your oven to 350°F (175°C). Line a 9×13-inch baking pan with parchment paper, leaving some overhang on the sides so you can easily lift the bars out later. Lightly grease the parchment.
2. Combine the melted butter and sugars.
   Add the melted butter, brown sugar, and granulated sugar to a large mixing bowl. Whisk for about 1–2 minutes, until smooth and glossy.
3. Add the sourdough starter.
   Stir in the sourdough discard until completely combined. You can use either active starter or discard; this recipe doesn’t require the starter to be bubbly.
4. Add the eggs and vanilla.
   Whisk in the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
5. Mix the dry ingredients.
   In a separate bowl, whisk together the flour, baking soda, and salt.
6. Combine the wet and dry ingredients.
   Gradually add the dry ingredients to the wet mixture. Stir with a spatula until just combined. The dough will be thick.

   Be careful not to overmix—the less you work the dough once the flour is added, the softer and chewier your cookie bars will be.

7. Add the chocolate.
   Fold in the chocolate chips and chocolate chunks, reserving a small handful to sprinkle over the top.
8. Transfer to the pan.
   Spread the dough evenly into the prepared baking pan. Since the dough is thick, gently press it into the corners with a spatula or lightly damp hands.
9. Add the finishing touch.
   Sprinkle the reserved chocolate chips and chunks over the surface. If you like the sweet-and-salty combination, add a small pinch of flaky sea salt.
10. Bake.
    Bake for approximately 25–30 minutes, or until the edges are golden brown and the center looks set but still slightly soft.

    Don’t wait until the center looks completely dry. The bars will continue cooking from residual heat as they cool, and slightly underbaking them is the secret to that soft, chewy center.

11. Cool completely.
    Let the cookie bars cool in the pan for at least 30–45 minutes before slicing. For especially clean slices, allow them to cool completely.
12. Slice and serve.
    Use the parchment overhang to lift the entire slab from the pan. Cut into squares or rectangles and serve.

Tips for the Best Sourdough Cookie Bars

• Use sourdough discard: This is an excellent discard recipe, so there’s no need to feed your starter first.
• Don’t overbake: The center should look just barely set when you remove the pan from the oven.
• Use chocolate chunks: A combination of chocolate chips and chopped chocolate creates pockets of melted chocolate throughout the bars.
• Brown the butter: For a deeper, nuttier flavor, brown the butter before making the recipe. Let it cool until warm rather than hot before adding the sugars.
• Add flaky salt: A little flaky sea salt on top makes the chocolate flavor stand out and cuts through the sweetness.
• Chill for thicker bars: If you prefer particularly thick cookie bars, refrigerate the prepared dough in the pan for 30–60 minutes before baking. You may need a few additional minutes of baking time.
• For extra chocolate: Add another ½ cup of chocolate chips or chunks if you want these to be seriously chocolate-packed.

Storage

Keep the cooled cookie bars in an airtight container at room temperature for 3–4 days.

For longer storage, wrap the bars tightly and freeze them for up to 3 months. Thaw at room temperature, or microwave individual bars for about 10–15 seconds to make the chocolate soft and gooey again.

Makes

24 cookie bars when cut into smaller squares, or about 16 larger bars.

Best served warm: Pop a bar in the microwave for a few seconds and serve it with a scoop of vanilla ice cream for an extra-decadent dessert.