Chewy Oatmeal Blondies are my go-to when I want a bar cookie that eats like a thick oatmeal cookie, but slices clean and looks neat on a plate. They’re buttery, brown sugar-y, and just sturdy enough to pack up for lunches or bring to a potluck.
The flavor is simple and classic: vanilla, warm molasses notes from brown sugar, and that hearty chew from oats. I like adding chocolate chips most of the time, but they’re also great plain if you want the oatmeal flavor to stand out.
For me, these are especially good for weekend baking and cookie trays when I don’t want to fuss with scooping dough. Cut them small for snacking, or bigger for a more dessert-y bar.
Why You’ll Love This Recipe
Soft and Chewy: The rolled oats give that real oatmeal-cookie chew, and the centers stay a little soft if you pull them on time.
One Bowl Friendly: You can mix this up fast without a mixer, which is nice when you just want bars and not a whole project.
Brown Sugar Flavor: These taste like the best part of a blondie—rich, buttery, and vanilla-forward—with a cozy oatmeal cookie vibe.
Easy to Slice: An 8-inch pan makes thick bars, and they cut into clean squares once they’re fully cooled.
Make Them Your Way: Chocolate chips are great, but raisins, butterscotch chips, or white chocolate all work too. Nuts are optional if you like a little crunch.
Ingredients You’ll Need
Batter
- Unsalted butter: Melted butter makes these quick, and it gives the bars that dense, chewy texture. Let it cool a bit so it doesn’t scramble the eggs.
- Light brown sugar: This is the main flavor here, so use fresh, soft brown sugar if you can. Dark brown sugar works too if you want a deeper molasses taste.
- Eggs: Room temperature is easier to whisk in smoothly, but cold eggs will still work. The eggs help the bars set without turning cakey.
- Vanilla extract: I like a full vanilla flavor in blondies, so don’t skip it. Use real extract if you have it.
- All-purpose flour: Regular flour is perfect here. Measure it lightly so the bars don’t get dry.
- Baking powder: Just enough lift to keep the middle tender instead of dense and greasy.
- Fine salt: This keeps the sweetness in check and makes the brown sugar taste stronger. If you only have kosher salt, use a little more.
- Old fashioned rolled oats: This is where the chew comes from. Quick oats will work in a pinch, but the texture won’t be the same.
- Ground cinnamon (optional): I add it when I want a more “oatmeal cookie” feel. If you’re using white chocolate or butterscotch chips, cinnamon is especially nice.
Mix ins
- Semisweet chocolate chips: Semisweet is my go-to because it doesn’t make the bars overly sweet. Milk chocolate is fine if that’s what you have.
- Walnuts or pecans (optional): Adds crunch and a little toasty flavor. Chop them so they’re easy to slice through.
Recipe Instructions
- Preheat the oven: Heat the oven to 350°F. Line an 8-inch square baking pan with parchment paper and lightly grease it.
- Mix the butter and sugar: In a large bowl, whisk the melted (slightly cooled) butter and brown sugar until smooth and well blended.
- Add the eggs and vanilla: Whisk in the eggs and vanilla extract until the mixture looks glossy and evenly combined.
- Add the dry ingredients: Stir in the flour, baking powder, salt, rolled oats, and cinnamon (if using) just until you no longer see dry flour.
- Fold in the mix-ins: Fold in the chocolate chips and nuts, if using, until they’re spread through the batter.
- Spread the batter: Scrape the batter into the pan and spread it into an even layer, all the way to the corners.
- Bake: Bake for 20 to 25 minutes, until the edges are set and the center is still slightly soft.
- Let cool: Cool completely in the pan for clean cuts, then slice and serve.
Some of my tips!
This is the part that really makes a difference. If you only read one section, make it this one because this is where I share the little trick that helps the recipe turn out so well.
Recipe Tips & Tricks
Use old fashioned oats. They give the best chew and that classic oatmeal-cookie texture. Quick oats make the bars softer and less hearty.
Don’t overmix once the flour goes in. Stir just until the flour disappears, then stop. Overmixing is what makes blondies tough.
Pull them when the center still looks a little soft. The edges should look set, but the middle shouldn’t look fully firm. They finish setting as they cool.
Try browning the butter for deeper flavor. It gives a nutty taste that’s really good with oats and chocolate. Just cool it down before you whisk it into the sugar.
Let them cool completely before slicing. Warm blondies are messy to cut, and they can seem underbaked even when they’re not. Once cool, they slice into neat squares.
Make some touches!
There are plenty of easy ways to serve this depending on the occasion. Keep it simple, or add a few small touches to make it feel a little more special.
Serving Suggestions
- Milk: A cold glass of milk is classic with these. It’s especially good if you go heavy on the chocolate chips.
- Coffee: These are really nice with coffee or a latte. The brown sugar and vanilla taste great with something bitter.
- Ice cream: Serve a square with vanilla ice cream if you want a more dessert-y plate. I like it best when the blondie is at room temp and the ice cream is cold.
- Fruit: Fresh berries are a simple side, especially strawberries or raspberries. It keeps the plate from feeling too heavy.
Save it for later
This section covers how to store leftovers and what parts of the recipe you can prepare ahead of time.
Storage and Make Ahead
Store leftovers covered at room temperature for up to 4 days. I usually keep them in an airtight container so the edges don’t dry out.
If you want to make this recipe ahead, bake the bars the day before and leave them covered on the counter. They actually slice even cleaner the next day.
If you want them longer than a few days, freeze individual portions or freeze the whole slab wrapped well. Thaw at room temperature, or thaw in the fridge overnight.
For that just-baked feel, warm a square in the microwave for a few seconds. It softens the chocolate chips again and brings back the chew.
A few quick answers
This section covers a few extra details that may help before you head to the recipe card.
Recipe FAQs
Can I use quick oats instead of old fashioned?
You can, but the texture will be different. Quick oats make the bars softer and a little more uniform, while old fashioned oats give the best chew and a more “oatmeal cookie” bite.
How do I know when oatmeal blondies are done?
I look for set, lightly browned edges and a center that still looks slightly soft. If the whole pan looks firm and dry, they’re usually heading toward overbaked.
Can I brown the butter?
Yes, and it’s a great upgrade if you have a few extra minutes. Brown the butter, then let it cool so it’s not piping hot before you whisk it into the brown sugar.
What other mix-ins work besides chocolate chips?
Raisins, butterscotch chips, or white chocolate chips all work well here. If you’re swapping in something sweeter like butterscotch, I usually keep the salt as-is.
Why did my blondies turn out dry?
The most common reasons are overbaking or packing in too much flour. Bake just until the edges are set and measure flour lightly (spoon and level, if you tend to scoop straight from the bag).
You might also like
Before you go, take a look at a few other recipes below the recipe card. They use similar ingredients in a different way and are worth saving too.
MORE DINNER RECIPES TO TRY
Chewy Oatmeal Blondies
INGREDIENTS
Batter
- 1 cup unsalted butter melted and slightly cooled
- 1 1 2 cups light brown sugar packed
- 2 large eggs room temperature
- 2 tsp vanilla extract
- 1 1 4 cups all purpose flour
- 1 tsp baking powder
- 1 2 tsp fine salt
- 1 1 2 cups old fashioned rolled oats
- 1 2 tsp ground cinnamon optional.
Mix ins
- 3 4 cup semisweet chocolate chips
- 1 2 cup chopped walnuts or pecans optional.
INSTRUCTIONS
Prep
- heat oven to 350 F
- line an 8 inch square baking pan with parchment and lightly grease
- whisk melted butter and brown sugar until smooth
- whisk in eggs and vanilla until glossy.
Bake and cool
- stir in flour baking powder salt oats and cinnamon just until combined
- fold in chocolate chips and nuts if using
- spread batter evenly in pan
- bake until edges are set and center is slightly soft 20 to 25 minutes
- cool completely in pan for clean cuts then slice and serve.
