These Oatmeal Cookie Bars are the ultimate treat, combining chewy oats, rich buttery flavor, and a hint of sweetness in every bite. Perfectly balanced with a soft, slightly crisp texture, they’re ideal for satisfying your dessert cravings or pairing with your morning coffee. Ready in just 55 minutes, they’re a fuss-free indulgence that feels homemade and comforting.
Packed with wholesome oats and a touch of decadence, these bars are as nourishing as they are delicious. The golden edges and gooey center create a delightful contrast, while the warm, caramel-like aroma fills your kitchen as they bake. Whether you’re sharing them with friends or keeping them all to yourself, these bars are sure to become a favorite in your recipe collection.
What You’ll Need for Oatmeal Cookie Bars
- 1 cup (226 g) butter, melted
- 1 cup (200 g) light brown sugar, tightly packed
- ½ cup (100 g) sugar
- 2 large eggs + 1 large egg yolk
- 1 ½ teaspoons vanilla extract
- 1 ¼ cup (157 g) all-purpose flour
- 2 teaspoons cornstarch (cornflour in the UK)
- ½ teaspoon baking powder
- ¾ teaspoon salt
- ¼-½ teaspoon ground cinnamon (optional, for a hint of warmth)
- 3 cups (285 g) old-fashioned rolled oats
- 1 ½ cups (255 g) chocolate chips (optional, mix semisweet, milk chocolate, or butterscotch chips for variety)
How to Make Oatmeal Cookie Bars
- Preheat your oven to 350°F (175°C). Line a 9×9 metal baking pan with parchment paper or grease and flour the sides and bottom.
- In a large bowl, combine the melted butter, light brown sugar, and sugar. Stir until well combined.
- Add the eggs, egg yolk, and vanilla extract to the butter mixture. Stir until smooth and fully incorporated.
- In a separate bowl, whisk together the flour, cornstarch, baking powder, salt, and cinnamon (if using).
- Gradually add the dry ingredients to the wet ingredients, stirring until completely combined.
- Fold in the oats and chocolate chips (if using) until evenly distributed throughout the dough.
- Spread the dough evenly into the prepared baking pan. Use a spatula to smooth the top.
- Bake in the preheated oven for 35-40 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.
- Allow the bars to cool in the pan before slicing and serving. Enjoy!
Creative Toppings and Mix-Ins
Take your Oatmeal Cookie Bars to the next level by experimenting with toppings and mix-ins. Try adding a drizzle of melted white chocolate or caramel sauce for extra sweetness. For a crunchy twist, sprinkle chopped nuts like pecans or walnuts on top before baking. You can also swap out chocolate chips for dried fruit, such as cranberries or raisins, for a chewy, tangy flavor.
Perfect Pairings for Serving
These bars are delicious on their own, but they shine even more when paired with a cold glass of milk, a scoop of vanilla ice cream, or a warm cup of coffee. For a brunch treat, serve them alongside fresh fruit or yogurt. They’re also a great addition to dessert platters or as a sweet snack in lunchboxes.
Storage and Freshness Tips
Store your Oatmeal Cookie Bars in an airtight container at room temperature for up to 5 days. For longer storage, wrap them tightly in plastic wrap and freeze for up to 3 months. To reheat, pop them in the microwave for 10-15 seconds or warm them in a 300°F (150°C) oven for 5 minutes to restore that fresh-baked texture.
Quick Time-Saving Hacks
Short on time? Use a stand mixer to combine the butter and sugars quickly. You can also prep the dry ingredients the night before and store them in a sealed container. If you’re in a rush, press the dough into the pan and bake immediately—no need to chill it first. These bars are ready in under an hour, making them a perfect last-minute treat!
Recipe Variations to Try
Customize these bars to suit your taste! Swap the chocolate chips for peanut butter chips or white chocolate chunks. For a healthier twist, use coconut sugar instead of brown sugar and add shredded coconut. If you’re gluten-free, substitute the all-purpose flour with a gluten-free blend. The possibilities are endless!
Oatmeal Cookie Bars
Ingredients
- 1 cup butter melted
- 1 cup light brown sugar tightly packed
- ½ cup sugar
- 2 large eggs + 1 large egg yolk
- 1 ½ teaspoons vanilla extract
- 1 ¼ cup all-purpose flour
- 2 teaspoons cornstarch cornflour in UK
- ½ teaspoon baking powder
- ¾ teaspoon salt
- ¼-½ teaspoon ground cinnamon optional
- 3 cup old fashioned rolled oats
- 1 ½ cup chocolate chips optional, I did a mix of semisweet chocolate chips, milk chocolate chips, and butterscotch chips
Instructions
- Preheat oven to 350F (175C) and line a 9×9 metal baking pan with parchment paper or grease and flour the sides and bottom of the pan.
- Combine butter and sugars in a large bowl and stir until well-combined.
- Add eggs and vanilla extract and stir well.
- In a separate bowl, whisk together flour, cornstarch, baking powder, salt, and cinnamon (if using).
- Gradually add dry ingredients to wet until completely combined.
- Add oats and chocolate chips and stir until well combined.
- Spread cookie dough evenly into prepared baking pan and bake on 350F (175C) for 35-40 minutes or until a toothpick inserted in the center comes out clean or with a few moist crumbs.