Let’s be real for a second: weekday mornings can be absolute chaos. Between finding matching socks and getting everyone out the door, breakfast often becomes an afterthought. That’s precisely why I fell completely in love with this large batch baked oatmeal. It’s a total game-changer for anyone trying to feed a crowd or prep for the busy week ahead without losing their mind!
I used to stand over the stove stirring a single pot of oats, but then I realized I could double the recipe, throw it in a 9×13 pan, and have breakfast sorted for the entire week. This recipe is designed to serve 12 people (or provide 12 solid meal-prep servings), making it incredibly efficient. Plus, because it uses yogurt and eggs, it packs a protein punch that keeps you whole way longer than a standard bowl of cereal.
If you are looking for a breakfast that is freezer-friendly, packed with fiber, and genuinely delicious, you have come to the right place. Get ready to make your mornings so much smoother!
Table of Contents
Large Batch Baked Oatmeal (Serves 12)
Ingredients
For the Base
- 4 cups rolled oats old-fashioned, not quick oats
- 2 cups plain yogurt homemade or store-bought
- 1 cup milk dairy or non-dairy
- 1 cup water
- 4 large eggs
- ¾ cup sugar or substitute ½ cup maple syrup or honey
- ⅔ cup butter melted (or coconut oil)
- 1 tablespoon vanilla extract
- 1 tablespoon ground cinnamon
- 1 tablespoon baking powder
For the Mix-Ins (Choose Your Favorite)
- 2-3 cups fresh frozen, or dried fruit (blueberries, peaches, apples, cranberries, raisins)
- 1 cup chopped nuts pecans, walnuts, almonds
- 1 cup chocolate chips for a treat!
- Optional: 1½ cups fruit puree mashed banana, applesauce, or pumpkin puree—Note: reduce water to ½ cup if using puree
Instructions
- Mix the Wet Ingredients: In a large mixing bowl, whisk together the yogurt, milk, water, eggs, sugar, melted butter, vanilla extract, and cinnamon until smooth. If using fruit puree (like banana or pumpkin), whisk it in now.
- Prepare the Oats: In a separate medium bowl, sprinkle the baking powder over the rolled oats. Toss well to distribute the baking powder evenly—this ensures a fluffy texture!
- Combine: Pour the oat mixture into the wet ingredients. Stir gently until all oats are fully incorporated. The batter will be thick but pourable.
- Assemble: Lightly oil a 9×13-inch baking pan. Pour the batter in, spreading it evenly. Sprinkle your chosen mix-ins (fruit, nuts, or chocolate) on top and gently stir them into the batter.
Bake (Two Options):
- Immediate Bake: Preheat oven to 350°F (175°C). Bake for 1 hour until the top is golden brown and the center is set.
- Overnight/Cold Oven Method: Cover and refrigerate for up to 24 hours. When ready, place the cold pan into a cold oven. Turn oven to 350°F and bake for 1 hour 10 minutes total.
- Serve: Let cool for 5–10 minutes before cutting into squares. Serve warm with milk, yogurt, or maple syrup.
Notes
- Storage: Store leftovers in an airtight container in the fridge for up to 5 days.
- Freezing: Wrap individual cooled squares in plastic wrap and store in a freezer bag for up to 3 months. Thaw overnight or microwave for 30-60 seconds.
- Fruit Puree Note: If you add mashed banana or applesauce, remember to reduce the water in the recipe to ½ cup to prevent it from being too wet.
Nutrition
Ingredients
Here is Everything you need to whip up this hearty breakfast. I’ve stuck to standard pantry staples to keep things easy and budget-friendly.
- 4 cups rolled oats (Make sure to use old-fashioned, not quick oats, for the best texture)
- 2 cups plain yogurt (Homemade or store-bought both work perfectly)
- 1 cup milk (Feel free to use dairy or your favorite non-dairy alternative)
- 1 cup water
- 4 large eggs
- ¾ cup sugar (Or substitute with ½ cup maple syrup or honey if you prefer natural sweeteners)
- ⅔ cup butter, melted (Coconut oil is a great swap here, too)
- 1 tablespoon vanilla extract
- 1 tablespoon ground cinnamon
- 1 tablespoon baking powder
- For the Mix-Ins: 2-3 cups fruit (fresh/frozen), 1 cup nuts, or 1 cup chocolate chips
How to Make Large Batch Baked Oatmeal
This process is incredibly forgiving, so don’t stress if you aren’t a master baker. The goal here is a “dump and bake” style recipe that delivers maximum flavor with minimal effort.
1. Mix the Wet Ingredients
First, grab your largest mixing bowl. Remember, we are making a big batch here! Whisk together the yogurt, milk, water, eggs, sugar, melted butter, vanilla extract, and cinnamon until the mixture is smooth and homogeneous.
If you decide to use a fruit puree, such as mashed banana, applesauce, or pumpkin, to add extra moisture or flavor, go ahead and whisk it in right now. Creating this rich, creamy base first ensures that every bite of oatmeal will be moist and flavorful.
2. Prepare the Oats
In a separate medium bowl, take your rolled oats and sprinkle the baking powder over them. Please give it a good toss to ensure that the baking powder is distributed evenly.
Why do we do this? If you dump the baking powder straight into the wet mix, it might clump up. Mixing the dry oats first ensures that your baked oatmeal rises uniformly and has the perfect, fluffy texture we’re after, rather than turning out dense or heavy.
3. Combine Everything
Now for the satisfying part! Pour the oat mixture into the bowl with your wet ingredients. Stir it all gently but thoroughly. You want to ensure that every single oat is coated with the delicious yogurt and cinnamon mixture.
The batter will appear thick but pourable, with a consistency similar to that of a thick cake batter. It smells pretty amazing already.
4. Prepare the Pan & Add Mix-Ins
Lightly oil a 9×13-inch baking pan with butter or cooking spray. Pour the batter into the pan and spread it out evenly.
Now, sprinkle your chosen mix-ins over the top. Whether you’re using blueberries, walnuts, or chocolate chips, stir them gently into the batter right in the pan. This saves you from dirtying another bowl and ensures you get a little bit of goodness in every bite.
5. Bake Immediately or Use the Cold Oven Method
Here is where this recipe really shines for meal prep. You have two distinct options:
To Bake Immediately: Preheat your oven to 350°F. Once hot, bake for 1 hour until the top is golden brown and the center is set.
The Make-Ahead Strategy (Cold Oven Start): If you prepped this the night before (which I highly recommend for stress-free mornings!), cover the pan and keep it in the fridge for up to 24 hours. When you are ready to bake, place the cold pan into a COLD oven.
Important Tip: Putting a cold glass pan into a hot oven can cause it to crack. By starting cold and turning the stove to 350°F after the pan is inside, you protect your dish. Set your timer for 1 hour and 10 minutes in total, accounting for the preheating time.
6. Check for Doneness & Serve
You will know it’s ready when the kitchen smells like a bakery, and the top is beautifully golden brown. The edges should pull slightly away from the pan, and the center should be set, not jiggly.
Let it cool for about 5-10 minutes before slicing it into squares. It’s absolutely fantastic, warm, but honestly? It’s totally crave-worthy straight from the fridge, too!
Tips, Variations & Storage Instructions
I love this recipe because it is a blank canvas. While the base is solid, you can tweak it to fit whatever you have in your pantry. Here are a few ways to make this meal prep baked oatmeal work for you.
Flavor Variations to Try
- Apple Pie: Use diced apples as your fruit and add a pinch of nutmeg with the cinnamon.
- Berry Blast: Use a mix of frozen blueberries, raspberries, and blackberries.
- Pumpkin Spice: Replace the fruit with pumpkin puree (reduce the water to ½ cup) and add pumpkin pie spice.
Storage & Freezing
Since we are focusing on large-batch baked oatmeal, knowing how to store it is key.
- Fridge: Store leftovers in an airtight container in the refrigerator for up to 5 days.
- Freezer: This is totally freezer-friendly! Cut the baked oatmeal into individual portions, wrap them in plastic wrap or parchment paper, and store them in a freezer-safe bag for up to 3 months.
- Reheating: Microwave a square for 30-60 seconds for a quick, hot breakfast.
Nutrition Note
- Nutritional information is approximate and may vary based on ingredients used.
- Calories: ~250 per serving
- Protein: ~8g
- Fiber: ~4g
- Note: Using Greek yogurt can further boost the protein content.
What to Serve With Baked Oatmeal
While this oatmeal is filling enough to stand on its own, sometimes it’s nice to round out the meal, especially for a weekend brunch.
- Fresh Fruit Salad: The brightness of fresh melon or citrus pairs perfectly with the warm, dense texture of the oats.
- Yogurt Dollop: I love adding a cool dollop of Greek yogurt on top of a warm square. It adds creaminess and extra protein.
- Savory Sides: If you crave that sweet-and-salty combo, serve this alongside bacon or turkey sausage.
- Smoothies: If you are feeding active kids or need a massive nutrient boost, a green smoothie is a great partner for this dish.
FAQs
How long does baked oatmeal last?
Baked oatmeal is an excellent choice for meal prep, as it lasts up to 5 days in the refrigerator when stored in an airtight container. It actually tends to get softer and more custard-like as it sits!
Can you freeze baked oatmeal?
Absolutely! This recipe is specifically designed to be freezer-friendly. I recommend slicing the cooled oatmeal into individual servings before freezing, so you can grab just what you need for a quick, make-aheadbreakfast.
Can I make a big batch of oatmeal for the week?
Yes, and that is the best part about this recipe! Using a 9×13 pan allows you to bake 12 servings at once. It saves you time on washing dishes and ensures you have a healthy, homemade breakfast ready every single morning.
Conclusion
There you have it, a large batch baked oatmeal recipe that is as practical as it is delicious. Whether you are feeding a hungry family or just trying to get your own meal prep sorted, this recipe is a total lifesaver.
I really hope you give this a try! If you do, let me know what mix-ins you used. I’m always looking for new flavor combos to try out in my own kitchen. Happy baking!
