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These are the ultimate cookie bars! Delicious, gooey oatmeal chocolate chunk cookie bars are made even better with the complex, caramely flavor of brown butter. Better make a double batch – these will fly off the plate anywhere you take them.
Aren’t you just drooling for one of these bars?? If so, I have good news for you – you can be digging into one in under an hour! Let’s learn how to make them.
What’s Brown Butter?
Browning your butter is a simple step that takes just 5 minutes and adds so much flavor to these incredible bars! Add your butter to a skillet over medium heat. Once the butter is melted, keep heating it, stirring, until it turns a golden brown color and develops an amazing caramely, nutty aroma. Remove it from the heat at this point so you don’t burn it, and proceed to use it in any dessert that calls for butter to instantly amp up the flavor!
If using in a dessert that calls for melted butter, use it as is. And, if using in a recipe that calls for butter softened to room temp, you can add it to a small bowl and chill it in the fridge until it’s back to the right consistency.
How to Make Brown Butter Oatmeal Chocolate Chunk Cookie Bars:
Once your butter is browned, whisk it together with sugar, vanilla, and eggs in a medium mixing bowl. (If you’re new around here, yes this is the mixing bowl for which my blog is named!)
Next, stir in your dry ingredients – flour, oats, a hint of cinnamon (trust me – it’s so good with the flavor of the brown butter!), baking soda, and a pinch of salt. Chop up some semi-sweet chocolate to make those big, beautiful chocolate puddles and stir those in last!
Press your cookie dough into a lined 9×9 pan, and bake for about 18 minutes. See? I told you these would be quick. 🙂
Once they’re out of the oven, wait as long as you possibly can before cutting in – but they are SO good while they’re still warm from the oven. I wait about 30 mins to 1 hour before cutting into mine, so they can set up a bit, while still staying plentyy warm and gooey.
You must finish these off with a sprinkle of flaky sea salt! It’s the perfect compliment to the chocolate and takes these right over the top. A cold glass of milk is also a must here. Or even a cup of coffee! Mmm can’t you just imagine snacking on these on a chilly fall day with a hot cup of coffee in hand?
Hopefully I’ve convinced you to add these to your baking list. I know you’ll instantly fall in love with these bars, just like we did! Once these are devoured, try my Fireworks M&M Cookie Bars!
Happy baking!
Brown Butter Chocolate Chunk Oatmeal Cookie Bars
Ingredients
- 9 tbsp salted butter, I prefer salted, you can use unsalted if desired
- 1/2 cup light brown sugar, packed
- 1/4 cup granulated sugar
- 1 large egg
- 1/2 tsp vanilla extract
- 3/4 cup all-purpose flour
- 1/2 tsp baking soda
- 3/4 tsp cinnamon, See note
- 1/4 tsp nutmeg, See note
- pinch ground cloves, See note
- 1/4 tsp salt
- 1 and 1/2 cup old-fashioned whole rolled oats
- 6 ounces semi-sweet chocolate, roughly chopped into chunks
Instructions
- Prep: Preheat your oven to 350 degrees F. Line a 9x9 pan with parchment paper.
- Brown the Butter: Add the butter to a skillet over medium heat. Once melted, turn the heat to medium-low, and continue cooking the butter, stirring constantly. The butter will get foamy and bubbly, and then turn a deep golden shade with a nutty, caramely aroma. (This will take about 5-6 minutes once the butter has melted.) Once the butter reaches this stage, remove it from the heat.
- Make the Cookie Bars: Add the brown butter to a medium mixing bowl, making sure to scrape all of it from the pan, including the little brown bits. Whisk in the sugars, then whisk in the eggs and vanilla. Stir in the dry ingredients - the flour, baking soda, spices, salt, and oats. Stir in the chocolate chunks last. Note: You can leave out the spices if desired, but they are honestly SO good in these bars, even if you might not think they "go" with the chocolate. You could also just add a pinch or two of cinnamon if you don't want to completely omit the spices.
- Bake: Spread the batter evenly in your prepared pan. Bake for 16-19 minutes. A toothpick inserted into the center should come out clean or have some moist crumbs, but not wet batter. The bars will look a bit underdone, but will set up more as they cool.
- Serve + Store: Let bars cool for about an hour before cutting into them. They're so good warm from the oven, with a glass of milk! Store leftovers (once cooled) in an airtight container at room temp for 4-5 days, or in the fridge for longer. Gently reheat squares if you love to eat them warm (like we do!).
So soft and cozy!
Thanks so much, Olivia!
If I wanted to make a double batch, would I just make it in a 9×13 pan?
Hi Kelcee, yes! Double the recipe and bake in a 9×13 pan. Please be sure to let me know how you like the recipe. 🙂
Love these! One bowl and so easy to make. We weren’t sure about the spices at first but so glad we added them. They are subtle but add depth. The bars stay soft once cooled and are amazing!
So glad you enjoyed these, Cara! 🙂
These are dynamite. Adding the cinnamon, cloves, and nutmeg is reminiscent of pumpkin pie spice so it adds a warmth to these bars but just enough. They have a light crust and are soft and chewy inside. Who doesn’t love the idea of basically one big delicious chocolate chip cookie in bar form. I could eat the whole thing in a sitting but I’ll leave*some* for others.
So glad you loved these bars Kim! Thanks for that incredible review 🙂 Happy baking!