These tender, soft, and decadent Oatmeal Chocolate Chip Blondies with Buttercream Frosting are the perfect treat to enjoy all week long. They taste delicious with a tall glass of cold milk!
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oatmeal + chocolate = a decadent combination
Did you know that January was National Oatmeal Month? I didn't either, but better late than never! 😜 Let’s celebrate with these Oatmeal Chocolate Chip Blondies with Buttercream Frosting!
If blondies and cookie cake had a baby, it would be these blondie bars. They're so tender, soft, and decadent—and the addition of some chocolate chips and fresh buttercream makes them even more delicious! You could even swap the chocolate chips for some raisins if you love the classic combo.
I love to enjoy these blondie bars with a tall glass of milk. It makes for such a wholesome snack. You won't regret making a batch to enjoy all week long!
Ingredients for Oatmeal Chocolate Chip Blondies
Butter: Leave this out on the counter so it comes to room temperature.
Sugar: Grab both brown sugar and white cane sugar.
Eggs: These will give our batter structure.
Vanilla Extract: I love the little hints of vanilla in these blondies.
Oat Flour: I used Bob’s Red Mill brand. You could also make your own by pulsing some rolled oats.
Baking Powder: To help our blondies rise.
Rolled Oats: I love using oatmeal in baking! Such yummy flavor and texture.
Chocolate Chips: I used mini chocolate chips. But feel free to use whatever you like.
Powdered Sugar: This will sweeten up our icing.
Almond Milk: We'll use this to help make our frosting.
Kitchen equipment & tools needed
To make these Oatmeal Chocolate Chip Blondies with Buttercream Frosting, you'll need a sauce pot, handheld mixer, mixing bowl, measuring cups and spoons, rubber spatula, 9x13 baking dish, parchment paper, plastic bag for piping (or a piping set), and scissors.
How to make these Oatmeal Chocolate Chip Blondies
- Preheat the oven to 350°F.
- In a large mixing bowl, beat together room temperature butter, brown sugar, and white sugar with a hand mixer. It took me about 3-5 minutes.
- Next, add in eggs and vanilla extract. Then, beat again.
- Pour in the oat flour, salt, baking powder, and rolled oats. Before mixing the batter again, lightly stir the dry ingredients on top.
- Combine wet and dry ingredients. You'll need to crank up the speed that arm strength. This will be a thick batter.
- Fold the chocolate chips into the batter with a rubber spatula.
- Grease a 9x13 Pyrex baking dish and pour in the batter. You may need to spray the rubber spatula with cooking grease so you can spread it easier. I used two butter knives to pull the batter to all sides of the pan.
- Bake 25-30 minutes or until a toothpick inserted in the center comes out clean.
- While the blondies bake, let's make the frosting. Beat together all ingredients in a mixing bowl. Start with 1 tablespoon of almond milk and continually add 1 tablespoon until the frosting is blended. You may need more or less of the almond milk, so keep an eye on it. I used a piping bag & frosting tip to get the detail on these blondies. You can easily use a rubber spatula to spread in on the blondies, too. Whatever works for you!
You can also watch the Oatmeal Chocolate Chip Blondie Web Story here!
Blondie tip: brown your butter
Browning butter is the process of taking regular butter just past its melting point to toast the milk solids. Doing this brings out the nuttier, richer, and caramel flavors of butter and really takes this recipe up a notch! Here’s the details on how to do it:
- You’ll need a small saucepan and whisk or spoon. I suggest a stainless steel or lighter color pan so you can see when the butter begins to change in color.
- Heat your pan over medium-high heat. Cut your butter into slices and add it to the heated pan. It’s best to use unsalted butter for this.
- Allow your butter to melt, stirring frequently to keep milk solids from sticking to the bottom of your pan.
- After a couple of minutes, your butter should begin to foam and browned specks should appear. Watch your butter closely! It should turn from yellow to a golden brown.
- Once the butter becomes a deep golden brown, transfer to a heat-proof bowl. This will stop the cooking process.
Burnt butter, which will leave black bits on the bottom of your pan, will have a very bitter flavor. If this happens, unfortunately, you'll need to toss it and try again. If you are nervous about this process, I recommend following the same steps on a lower heat to slow down the cooking process.
Here’s a quick video if you’re looking for a visual.
Note that some of the butter evaporates while it’s browning, so you end up with slightly less brown butter compared to the amount of butter you started with. A good rule of thumb is for every stick (8 tablespoons) of browned butter, you need an extra tablespoon of solid butter to make it.
Oatmeal Chocolate Chip Blondies Q+A
What's the best way to keep these blondies fresh?
Here's a tip that my family has been practicing since I was a kid: Keep a piece of sandwich bread in the same container as your blondies. A large Tupperware is best. I usually use the end slice of a loaf that is likely going in the trash anyway. All of the moisture in the bread will be drawn out by the blondies to keep them nice and soft.
Looking to make them more ooey gooey?
Reduce the amount of oat flour by ⅓ cup. It will give the blondies more of a edible cookie dough texture, especially in the center. I tested it like that the first time and Jack LOVED them.
Can I make my own oat flour?
Yes! Throw rolled oats in a food processor and pulse. If your food processor is not high powered, however, you may want to consider buying your oat flour pre-ground. If you can't achieve a very fine flour, the texture of your blondies will be compromised.
Can I use brown butter in these blondies?
You can! It will help you achieve a bolder and richer flavor. I've included some instructions above.
What other add-ins do you suggest?
Chocolate chips are only the beginning! Since these blondies are oat flour based, my mind first goes to raisins. Adding some walnuts, pecans, or other nut of choice would add some texture. You could also try adding peanut butter chips, butterscotch chips, or white chocolate chips. Heck, try some chopped up candy bars!
Other sweet treats you might like
Peanut Butter Monster Cookie Recipe
Oatmeal Chocolate Chip Blondies Recipe
Equipment
- Sauce pot
- Handheld mixer
- Mixing bowls
- Measuring cups and spoons
- Rubber Spatula
- 9x13 baking dish
- parchment paper
- plastic bag for piping
- scissors
Ingredients
For the blondies
- 1 stick room temperature butter
- 1 cup brown sugar
- ½ cup white cane sugar
- 2 eggs
- 1 tsp vanilla extract
- 2 ⅓ cups oat flour
- 1 ½ tsp baking powder
- 1 cup rolled oats
- ½ cup mini chocolate chips
For the frosting
- ⅓ cup room temperature butter
- 1 ½ cup powdered sugar
- 1-3 tablespoons almond milk
Instructions
- Preheat the oven to 350°F.
- In a large mixing bowl, beat together room temperature butter, brown sugar, and white sugar with a hand mixer. It took me about 3-5 minutes.
- Next, add in eggs and vanilla extract. Then, beat again.
- Pour in the oat flour, salt, baking powder, and rolled oats. Before mixing the batter again, lightly stir the dry ingredients on top.
- Combine wet and dry ingredients. You'll need to crank up the speed that arm strength. This will be a thick batter.
- Fold the chocolate chips into the batter with a rubber spatula.
- Grease a 9x13 Pyrex baking dish and pour in the batter. You may need to spray the rubber spatula with cooking grease so you can spread it easier. I used two butter knives to pull the batter to all sides of the pan.
- Bake 25-30 minutes or until a toothpick inserted in the center comes out clean.
- While the blondies bake, let's make the frosting. Beat together all ingredients in a mixing bowl. Start with 1 tablespoon of almond milk and continually add 1 tablespoon until the frosting is blended. You may need more or less of the almond milk, so keep an eye on it. I used a piping bag & frosting tip to get the detail on these blondies. You can easily use a rubber spatula to spread in on the blondies, too. Whatever works for you!
Notes
I’d love to hear your thoughts in the comments below. It’s my passion to create dishes that can be shared with others. Tell me something you loved, something that you think it might need, or just say hi!
Looking for this in MyFitnessPal?
If you're using MyFitnessPal, search 'A Paige Of Positivity' and find Oat Flour Chocolate Chip Blondies
1 blondie: 61 grams Carbs | 12 grams Fat | 6 grams Protein
**Disclaimer: for most accurate macronutrients and caloric breakdown, it is recommended that you input each ingredient into your MyFitnessPal food diary.
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5 stars on these FOR SURE. They were so good!! I wish I used less oat flour to get a more gooey texture. And I used oat milk instead of almond milk for the frosting - still wonderful.