These Sourdough Pumpkin Oatmeal Cookies are an easy fall dessert made with sourdough discard, rolled oats, and plenty of pumpkin spice. They're soft, chewy, and cozy... basically everything you want in a pumpkin cookie!
In a medium bowl, whisk together the rolled oats, flour, pumpkin pie spice, baking soda, and kosher salt. Set aside.
1 ½ cups (120 grams) rolled oats, 1 cup (120 grams) all-purpose flour, 1 teaspoon pumpkin pie spice, ½ teaspoon baking soda, ½ teaspoon Diamond Crystal Kosher Salt
In a large bowl, use a hand mixer or stand mixer to beat the softened butter, brown sugar, and granulated sugar until smooth and creamy. Add the egg and beat until light and fluffy. Mix in the pumpkin puree, sourdough discard, and vanilla extract until well combined.
½ cup (113 grams, 1 stick) unsalted butter, 6 tablespoons (75 grams) brown sugar, ¼ cup (50 grams) granulated sugar, 1 large egg, ¼ cup (60 grams) pumpkin puree, ¼ cup (50 grams) sourdough starter discard, 1 teaspoon vanilla extract
The mixture may look slightly curdled after adding the pumpkin and sourdough discard. This is normal.
Add the dry ingredients to the wet ingredients and mix just until no dry flour remains. Gently fold in any optional mix-ins, such as chocolate chips, nuts, seeds, or dried fruit. Cover and refrigerate the dough for at least 1 hour, or up to 2 days. Chilling firms up the butter and allows the oats to absorb some of the moisture, resulting in softer, chewier cookies.
½-1 cup mix-ins (chocolate chips, nuts, seeds, dried fruit, etc.)
About 20 minutes before baking, preheat the oven to 350°F and line a rimmed baking sheet with parchment paper. Scoop tablespoon-sized portions of chilled dough onto the prepared baking sheet, leaving about 2 inches between each cookie.
Bake for 9–11 minutes, or until the edges are lightly golden and the centers look just set. Don't worry if the centers still look slightly soft—they'll continue to firm up as the cookies cool.
Let the cookies cool on the baking sheet for 5 minutes, then transfer them to a wire rack to cool completely.
Notes
Storage: Store in an airtight container at room temperature for up to 4 days or freeze for up to 3 months.