Ingredients
- 1 cup 226g unsalted butter, softened
- 1 cup 200g light brown sugar, packed
- ½ cup 100g granulated sugar
- 2 large eggs room temperature
- 1½ teaspoons vanilla extract
- 1¾ cups 215g all-purpose flour
- 2 teaspoons cornstarch
- 1 teaspoon baking soda
- ¾ teaspoon salt
- ¾ teaspoon ground cinnamon
- 3 cups 285g old-fashioned rolled oats
- 1½ cups mix-ins chocolate chips, raisins, or nuts, optional
Instructions
- Beat the butter in a large bowl using an electric mixer for about 30 seconds until smooth.
- Add both sugars and beat for 2-3 minutes until light and fluffy, scraping down the sides of the bowl as needed.
- Beat in eggs one at a time, then add vanilla extract and mix well.
- In a separate bowl, whisk together flour, cornstarch, baking soda, salt, and cinnamon.
- Gradually add the flour mixture to the butter mixture, mixing on low speed until just combined.
- Stir in the oats until evenly distributed. If using mix-ins, fold them in now.
- Cover the dough and refrigerate for at least 30 minutes (or up to 3 days).
- Preheat oven to 375°F (190°C). Line baking sheets with parchment paper.
- Scoop chilled dough using a 2-tablespoon cookie scoop and place on prepared baking sheets, spacing cookies about 2 inches apart.
- Bake for 10-12 minutes until edges are lightly golden but centers still look slightly underdone.
- Allow cookies to cool completely on the baking sheet.
Notes
- For extra chewy cookies, use dark brown sugar instead of light.
- Don’t overbake! The cookies will continue to set as they cool on the hot baking sheet.
- Store in an airtight container at room temperature for up to 5 days.
- Dough can be frozen for up to 3 months.