Oatmeal Chocolate Chip Cookie Bars
Soft and chewy with crisp edges and tender, gooey centers, these Oatmeal Chocolate Chip Cookie Bars are the ultimate treat. Each bite is packed with toasty old-fashioned oats and melty pockets of chocolate — a mix of semi-sweet chunks and milk chocolate chips for the perfect balance. They have that nostalgic, warm-and-cozy feel, and a sprinkle of flaky sea salt brings it all together. Best of all, they’re made in just one bowl and come together quickly and easily.
Why You’ll Love These Oatmeal Cookie Bars
These Oatmeal Chocolate Chip Cookie Bars have me ready to convert all my cookie recipes into cookie bars — they’re that delicious. They’re everything you love about a classic cookie — just easier (and honestly, even better in my opinion). Baked in an 8×8-inch pan, they stay thick and gooey with crisp edge pieces and super soft center slices, so there’s something for everyone. Made in just one bowl, there’s no scooping required — simply spread the dough into a pan, bake, and slice. A touch of honey keeps the bars extra tender and helps them stay fresh for days (a little bakery trick I’ve learned along the way). Best of all, this recipe works as a base for whatever mix-ins or variations you love, making it a versatile staple to keep on hand.
Ingredient Overview
- Butter & Oil: Melted butter adds rich flavor, while canola oil keeps the bars extra soft and tender for days.
- Dark Brown Sugar & Granulated Sugar: More brown sugar than granulated sugar gives these bars their chewy texture. I like using dark brown sugar because it adds a deeper, richer flavor.
- Honey: Just one tablespoon helps retain moisture after baking, keeping the bars soft and fresh longer — a simple bakery trick I learned and use in a lot of my cookie recipes.
- Egg & Egg Yolk: The extra yolk adds richness and creates a more tender, indulgent texture.
- Old-Fashioned Oats: Use old-fashioned oats, not quick oats! They hold their shape and stay chewy for the best texture.
- Semi-Sweet & Milk Chocolate: A mix of semi-sweet chunks and milk chocolate chips creates the perfect balance of rich and sweet, with chocolate in every bite!
- Flaky Sea Salt: A generous sprinkle of flaky sea salt balances the sweetness and finishes the bars beautifully.
Step-by-Step Instructions
1. Preheat the oven to 350°F. Lightly spray an 8×8-inch baking pan and line it with parchment paper for easy removal.
2. Melt the butter and let it cool slightly. Whisk in the canola oil, brown sugar, and granulated sugar until smooth.
3. Add the egg, egg yolk, honey, and vanilla, whisking until fully combined.
4. Switch to a spatula and fold in the flour, oats, baking soda, and salt until mostly combined. Add the chopped semi-sweet chocolate and milk chocolate chips, reserving a small handful for the top. Mix just until incorporated.
5. Spread the dough evenly into the prepared pan, smoothing it to the edges without pressing it down too firmly. Sprinkle the reserved chocolate over the top. Bake for 18-20 minutes, until the edges are lightly golden and the center is set but still slightly soft.
Do not overbake — slightly underbaking keeps the bars soft and gooey. For firmer, crispier edges, bake closer to 20-22 minutes.
6. Finish with flaky sea salt while still warm. Let cool completely before lifting from the pan and slicing into 16 bars.
Mix-in & Variations
This recipe works beautifully as a base, so feel free to make it your own! Just keep the total mix-ins to no more than 1 cup to maintain the bars’ texture and structure.
- Switch up the chocolate: Use dark, semi-sweet, or milk chocolate — chips or chopped bars both work. Stick with one type, or mix two as I did in this recipe.
- Add something fun: Try butterscotch chips, peanut butter chips, chopped peanut butter cups, M&M’s, or white chocolate. I’m excited to try a chocolate-peanut butter version myself!
- Go classic: Stir in chopped pecans or walnuts, or swap the chocolate for raisins for an oatmeal-raisin twist. A dash of cinnamon pairs beautifully with nuts and enhances the cozy oat flavor.
Blue Mountain Baker’s Tips
Line the pan with parchment for easy removal. Use two overlapping pieces so the bottom and all sides are covered, leaving a small overhang to lift the bars out cleanly.
Press extra chocolate on top before baking. Reserving a small handful to scatter over the surface creates those bakery-style pools of melty chocolate.
Slightly underbake for the perfect texture. Check the bars at 18 minutes. The centers should look just set but still soft. They’ll continue to firm up as they cool, giving you that chewy, gooey middle.
Cool before cutting. As tempting as it is, let the bars cool completely before slicing. They’ll firm up as they cool, giving you those perfectly clean and even cuts.
Oatmeal Chocolate Chip Cookie Bars FAQ
Yes — but I recommend doubling the recipe. If you use the same amount of batter in a 9×13-inch pan, the bars will be too thin.
Yes! Scoop the dough into balls and bake at 350°F for about 9–11 minutes, until the edges are set and the centers are still soft.
Yes. Substitute a 1:1 gluten-free baking flour, and be sure to use certified gluten-free old-fashioned oats. I recommend Bob’s Red Mill for reliable results.
If Somehow You Have Leftovers…
- These bars stay soft and chewy for 3-5 days at room temperature in an airtight container.
- If you’d like to keep them longer, refrigerate in an airtight container for up to 1 week. Let them come to room temperature before serving for the softest texture.
- To freeze, wrap the individual bars tightly in plastic wrap and store in a freezer-safe container or bag for up to 2 months. Thaw at room temperature before enjoying.
I hope you enjoy these Oatmeal Chocolate Chip Cookie Bars! If you make them or try a variation, leave a comment and let me know how they turned out.
Happy baking, and thanks so much for being here!
XO, Blue Mountain Baker 💙
Recipe Card
Oatmeal Chocolate Chip Cookie Bars
Equipment
- 8×8-inch baking pan
- parchment paper
- mixing bowl
- Whisk
- rubber spatula
- Measuring cups
- Measuring spoons
- Kitchen scale (optional)
Ingredients
- ½ cup butter, melted 113g
- 2 tablespoons canola oil 28g
- ¾ cup dark brown sugar 160g
- ¼ cup granulated sugar 50g
- 1 tablespoon honey 21g
- 2 teaspoons vanilla extract
- 1 egg
- 1 egg yolk
- 1 ¼ cup all-purpose flour 160g
- 1 ¼ cup old-fashioned oats 120g
- ½ teaspoon baking soda
- ½ teaspoon salt
- ½ cup semi-sweet chocolate, chopped 85g
- ½ cup milk chocolate chips 85g
- flaky sea salt for finishing
Instructions
- Preheat the oven to 350°F. Lightly spray an 8×8-inch baking pan with baking spray and line with parchment paper.
- In a medium mixing bowl, whisk together the melted and slightly cooled butter, canola oil, brown sugar, and granulated sugar until smooth and combined.
- Whisk in the egg, egg yolk, honey, and vanilla extract until fully incorporated.
- Add the flour, oats, baking soda, and salt, mixing just until combined. Fold in both chocolates, reserving a small handful to sprinkle on top.
- Gently spread the dough into the prepared pan, smoothing to the edges without packing it down. Sprinkle the reserved chocolate over the top. Bake for 18-20 minutes, until the edges are lightly golden and the center has puffed slightly.
- Finish with a sprinkle of flaky sea salt while still warm. Let cool completely, then lift out and slice into bars.
