This Peanut Butter Baked Oatmeal turns simple oats into a cozy, hearty breakfast the whole family loves. It’s warm, satisfying, and tastes a little like a peanut butter cookie and oatmeal had a baby – in the best possible way. Some people call it Amish Breakfast Casserole, which somehow makes me love it even more.
If you enjoy baked oatmeal, you’ll also want to try my Breakfast Casserole or Homemade Cake Donuts!
Why You’ll Love This Peanut Butter Baked Oatmeal
It’s truly a one-bowl wonder. Just mix everything together, pour it into a baking dish, and let the oven do the rest. The peanut butter makes it extra rich and comforting, but it’s also very flexible – you can easily leave it out or swap it for almond butter if needed.
The edges get beautifully golden while the center stays soft and gooey. And yes… that crack on top is completely normal and actually a good sign!
FAQs
Can I make this without peanut butter? Yes! Simply omit the peanut butter. The baked oatmeal will still be delicious. Feel free to add raisins, dried cranberries, or fresh berries for extra flavor.
Can I use old-fashioned rolled oats instead of quick oats? You can, but the texture will be a bit heartier and chewier. Quick oats give a softer, more cohesive result. If using rolled oats, add an extra 2-3 tablespoons of milk.
What’s the best pan to use? An 8×8-inch glass dish gives the softest, gooey texture. A metal pan works too but may brown the edges a little faster.
Can I make this gluten-free? Yes! Just use certified gluten-free oats and double-check that your baking powder is gluten-free.
Is this recipe very sweet? It has a pleasant sweetness similar to a peanut butter cookie. You can reduce the brown or granulated sugar by 1-2 tablespoons if you prefer it less sweet.
How to Make Ahead
This baked oatmeal is perfect for meal prep!
Full make-ahead: Bake the oatmeal, cool completely, cover, and refrigerate for up to 4 days.
Night before: Assemble the mixture, pour it into the baking dish, cover tightly, and refrigerate overnight. In the morning, let it sit on the counter while the oven preheats, then bake as directed (it may need 3-5 extra minutes).
How to Serve Baked Oatmeal
As you can see by the first picture in the blog post, we like a little organic maple syrup drizzled on top. Other fun variations are:
- fresh fruit such as banana or strawberry
- adding homemade whipped topping with raisins (my boys favorite)
- fresh vanilla yogurt
And, of course, we love it warm. Quite honestly, this dish has never made it to the “leftover” stage in our house, so I don’t even know if it reheats well! My gut says that yes, it would. Just pop it in the microwave and enjoy. 🙂
How to Store
Refrigerator: Store leftover baked oatmeal covered in the refrigerator for up to 4 days.
Freezer: Cut into portions, wrap tightly, and freeze for up to 2 months. Thaw overnight in the refrigerator.
Reheating: Warm individual portions in the microwave with a splash of milk for 30-60 seconds. For larger amounts, reheat in a 325°F oven until warmed through.
Baked Oatmeal
Ingredients
- 1 ½ cups quick cooking oats
- ¼ cup packed brown sugar
- ¼ cup granulated sugar
- ¾ cup milk
- ¼ cup melted butter
- ½ cup peanut butter (creamy or chunky works)
- 1 teaspoon vanilla
- 1 large egg
- 1 teaspoon baking powder
- ¾ teaspoon kosher salt (if using table salt use ½ teaspoon)
Instructions
- Preheat oven to 350°F. Put all the ingredients in a bowl and mix until combined. It will appear very wet.
- Pour mixture into baking dish. I used an 8×8 glass baking dish because I wanted a soft and gooey texture. (If you use a 9×13 pan they will be a little thinner and less gooey, but also more familiar and delicious.)
- Bake for 20-25 minutes or until the edges are golden brown. If it cracks on top don't worry, it's not overdone. An inserted toothpick should be removed with crumbs clinging to it.
- Serve warm.
Notes
Night before: Assemble the mixture, pour it into the baking dish, cover tightly, and refrigerate overnight. In the morning, let it sit on the counter while the oven preheats, then bake as directed (it may need 3-5 extra minutes).
Full make-ahead: Bake the oatmeal, cool completely, cover, and refrigerate for up to 4 days.
Did you make this recipe?
Thank you for making my recipe! You took pictures, right? Well go ahead and post them on Instagram! Be sure to mention me @iambaker and use the hashtag #YouAreBaker.
Images updated. Originally published in 2011.
I need to try this – looks so good!
baked oatmeal? you are a genius! i need to make a batch of this asap!
I will be making this very soon! It looks so yummy! And the possibilities are endless when you start adding different toppings. Thanks for another yummy idea!!
wow – this is a great idea – and I like that it is kid-approved – we are big oatmeal eaters.
We love oatmeal and THAT looks delicious! I have a recipe I’ve been wanting to try for Cherry Almond Baked Oatmeal…now I’m inspired! 🙂
What a great idea! I eat oatmeal every morning and never thought of baking it!
Yum! Is it wrong that I think this would be delicious topped with chocolate ganache?
I just want to crawl up with a bowl of this right now.
I have been keeping an eye on this blog for a little bit even though I am not a mom. I am jealous of the fact that you have people to test all these fun recipes out on. I live with just one other person who doesn’t like sweet breakfasts very much and I have two questions. I really want to try it since I love oatmeal.
1. How sweet did this turn out?
2. Would 5 minute quaker oats work?
Thanks!
I make a baked oatmeal that I love, but I will be needing to try this because I have a family who LOVES peanut butter! And basically, you are eating an oatmeal cookie for dinner or breakfast or whatever! YUM!!!!!