Sourdough Thumbprint Cookies With Lemon Curd

These sourdough thumbprint cookies are buttery, soft in the middle, lightly crisp around the edges and filled with glossy lemon curd - in other words, dangerously easy to "just try one" of. If you love bright, zingy bakes, these sourdough lemon cookies are a brilliant way to turn sourdough starter discard into something far more exciting than just another batch of crackers. 

Jump to:

• Recipe Highlights
• Ingredient Notes
• Step-By-Step Method
• Important Tips For Best Results
• Recipe FAQs
• Storage
• More Sourdough Discard Cookies
• Sourdough Thumbprint Cookies With Lemon Curd

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They've got all the charm of a classic thumbprint cookie, but with a proper sourdough twist. Think buttery sugar cookies with a subtle tangy flavour, a sparkling sugar coating, and a sunny lemon centre that makes them feel just a little bit more interesting than your average biscuit tin resident.

Ingredient Notes

• Unsalted Butter. Use softened butter, not melted butter, so it creams properly with the sugar and gives you that soft, tender cookie texture. Always use room temperature butter here.
• Granulated Sugar. You'll need white sugar in the dough and a little extra sweet granulated sugar for rolling. This gives the cookies a lovely sparkle and a slightly crisp exterior.
• Egg. One whole egg helps bind the dough and keeps the cookies soft. Unlike some other cookie recipes, you don't need just an egg yolk here.
• Vanilla Bean Paste. Adds warmth and depth. You can swap it for vanilla extract if that's what you've got.
• Sourdough Discard. Use sourdough starter discard straight from the fridge or at room temperature. It adds subtle tang and is a great way to reduce food waste. Since these sourdough cookies are not left to ferment, you can also use your active sourdough starter. 
• Flour. Plain flour / all-purpose flour is ideal here. You can replace a small portion with whole wheat flour if you'd like a slightly nuttier flavour, but don't overdo it or the cookies may become too dry.
• Baking Soda & Salt. A little baking soda gives gentle lift, while a pinch of salt balances the sweetness.
• Lemon Curd. The star of the show. You can use shop-bought or homemade. Just make sure it's fairly thick so it sits nicely in the center of each cookie without running everywhere.

Find ingredient quantities, detailed instructions and nutritional information in the recipe card at the bottom of the post. 

Step-By-Step Method

1. Cream the butter and sugar. Add the softened butter and sugar to a large mixing bowl and beat with an electric hand mixer or electric mixer for 2-3 minutes until light and fluffy.

2. Add the wet ingredients. Add the egg, vanilla and sourdough discard. Beat just until combined, scraping down the sides of the bowl if needed.

3. Mix the dry ingredients. In a separate bowl, stir together the flour, baking soda and salt.

4. Make the dough. Add the dry ingredients to the wet ingredients and fold together just until no dry flour remains. Don't overmix - you want tender cookies, not chewy bread dough.

5. Shape the cookies. Line a prepared baking sheet or cookie sheet with parchment paper. Scoop the dough into portions (about 18-20g per cookie) and roll into cookie dough balls using your hands or a cookie scoop.

6. Make the indent. Use your thumb, a small spoon, or the end of a wooden spoon to press a small indent into the centre of balls of dough. If the dough sticks, oil your tool/ thumb lightly.

7. Chill the cookies. Place the tray in the fridge and chill for 30 minutes.

9. Fill with lemon curd. Preheat the oven to 190 C (375F). Spoon a little lemon curd into each indent - about a small teaspoon is plenty. Don't overfill.

10. Bake. Bake until the edges are just turning golden (about 8-10 minutes).

11. Cool. Leave the cookies on the tray for 5-10 minutes, then transfer to a wire rack or cooling rack to cool completely.

Important Tips For Best Results

• Use properly softened butter. Cold butter won't cream properly, and melted butter will make the dough greasy. Softened butter gives the best texture.
• Chill the dough before baking. This is not optional if you want neat, thick cookies rather than flat little lemon puddles.
• Don't overmix once the flour goes in. Mix only until combined. Overmixing develops gluten and makes cookies tougher.
• Make the indent deep/wide enough. A shallow dent won't hold enough lemon curd. Aim for a proper little well, but don't press all the way through.
• Don't overfill with lemon curd. Tempting, I know. But if you fill them right to the top, the curd may bubble over in the oven.
• Re-shape if needed. If any cookies spread unevenly, you can gently nudge them back into shape with a spoon while they're still warm.
• Use thick lemon curd. A runny curd won't sit nicely in the centre. Thicker is better here.
• Bake just until lightly golden. These are meant to stay soft and buttery, not crunchy. Pull them out once the edges are lightly coloured.

Recipe FAQs

Storage

Store your sourdough thumbprint cookies in an airtight container at room temperature for up to 3 days.

Because of the lemon curd filling, they're best enjoyed fairly fresh, but they still hold up well for a couple of days.

Freezing

You can freeze them in two ways:

• Freeze unbaked dough balls (before filling), then thaw, indent and fill before baking
• Freeze baked cookies once fully cooled, though the lemon curd may lose a little of its shine after thawing

If freezing baked cookies, layer them carefully so the filling doesn't get squashed.

More Sourdough Discard Cookies

If you've got extra sourdough discard hanging about, there are plenty more sourdough discard recipes worth baking next - especially if you're partial to a good cookie and not remotely interested in wasting perfectly usable starter. From Sourdough Gingerbread Cookies to Buttery Sourdough Sugar Cookies and Sourdough Peanut Butter Blossoms, we have something for everyone!