Baked oats are a make-ahead healthy take on brunch casseroles that are typically bread centric.
Baked oatmeal is a sweet and gluten free breakfast by nature. This recipe uses a mix of fresh berries, which makes it a vibrant and tangy breakfast bake that appeals to both adults and children.
This casserole is perfect for a weekend brunch, or even a weekday morning breakfast. It takes less than ten minutes to mix the ingredients together and put in a dish to bake in the oven, where it will get golden and bubbly in about 45 minutes. Because it keeps well, it's perfect for eating hot out of the oven on Sunday morning with a spoon, then using as a grab and go handheld bar throughout the week.
There are also plenty of flavor and ingredient swaps you can make too. If you make this in the fall substitute diced apples and cinnamon, use only blueberries and skip the raspberries. If you’re vegan use flax eggs instead. Baked oatmeal is endlessly versatile and who doesn’t love a recipe you can make your own?
How to Make Baked Oatmeal
This straightforward recipe can be made without any strong culinary skills, and kids can easily help out in the process. Here are some tips to keep in mind when preparing a baked oatmeal casserole.
Baked oatmeal has a fairly firm texture, but it should never be dry. Conversely, it should turn out similar to a thick bread pudding. Think creamy and custardy, but firm enough to lift out of the pan with your hands if desired. Just like bread pudding, it should be removed from the oven when barely set, as it will set further while it cools.
To not offset the liquid ratio of this dish, fresh berries are the ideal choice. If you need to use frozen berries, be sure to thaw your fruit completely in advance and drain them well. Fold the frozen berries in with the other ingredients gently to make sure they don’t break down too much before baking.
Make It Vegan
To make this berry baked oatmeal vegan you can swap the milk and yogurt for plant-based versions and us an egg substitute instead of regular eggs.
To keep the portions correct you’ll want to use a vegan egg replacer that is a whole egg equivalent in volume, such as Follow Your Heart or Just Eggs, and not a starch replacer that only substitutes the thickening power of the eggs. The eggs here add volume, structure, and protein.
Swaps and Subs
This baked oatmeal is made with mixed berries, but you can take the basis of this recipe and use whatever flavor combinations you like.
Swap the blueberries and raspberries for:
- Blackberries and strawberries
- Apples and cinnamon
- Pears and ginger
- Mashed bananas
- Pumpkin puree and pumpkin pie spice
- Peanut butter
- Coconut flakes
- Grated zucchini
How to Serve
Serve this warm fresh from the oven, or serve leftovers chilled to be eaten as a handheld dish; it’s great for a grab and go breakfast that way, which makes the week’s breakfast meal prep a breeze.
It has a custard feel thanks to the milk and eggs and is best eaten with a spoon when warm or similar to bread pudding, it can be cut into squares. Be sure to use a large spatula or serving spoon to remove it from the pan.
This casserole is perfect on its own, with no accoutrements needed. However, toppings will enhance it, and you could even make a breakfast bar set up with the casserole as the base.
Perfect toppings for baked oatmeal include:
- Sour cream
- Fruit sauce
- Maple syrup
- Peanut butter
- Chopped nuts or seeds.
How It Keeps
Leftovers of this casserole hold up perfectly! Store them in a tightly sealed container rather than the original dish you baked in, so that the casserole won’t lose moisture in the refrigerator. Alternately, wrap each serving individually in plastic wrap and place in Tupperware and put in the fridge to enjoy a chilled oatmeal square later. Once refrigerated, it will keep for three to five days before drying out.
How to Reheat Baked Oatmeal
It can be baked ahead of time, stored in the casserole dish, then popped back in the oven to reheat the next day. To do that, reduce the baking time by ten minutes when baking ahead. If you’re feeding a crowd this recipe can also be doubled and baked in an 11x17 inch dish. If you double the recipe, add 10 to 15 minutes of baking time, depending on the depth of your casserole dish.
All About Oat Recipes
- Grab-and-Go Oatmeal Chia Cups
- Strawberry Oatmeal Muffins
- Slow Cooker Spiced Oatmeal
- Strawberry Buttermilk Overnight Oats
- Oatmeal Muffins with Raisins, Dates, and Walnuts
Baked Oatmeal with Mixed Berries
- 2 cups rolled oats
- 1/2 cups milk
- 3 eggs, beaten
- 2 tablespoons melted butter or olive oil
- 1/3 cup honey
- 1/2 cup whole-fat plain yogurt
- 1/2 teaspoon vanilla extract
- 3/4 teaspoon salt
- 1 cup blueberries, divided
- 1 cup raspberries, divided
Preheat your oven and prepare the baking dish:
Preheat your oven to 375°F. Grease with butter or lined a 9x9 baking dish with parchment.
Combine ingredients in a large mixing bowl:
In a large mixing bowl, add oats, milk, eggs, melted butter, honey, yogurt, vanilla, and salt. Stir with a fork or whisk to combine thoroughly.
Fold the berries into the mixture and move to casserole dish:
Fold 3/4 cup each of blueberries and raspberries into the mixture. Pour mixture into prepared casserole dish. Sprinkle all remaining berries over top.
Bake the oatmeal casserole for 45 minutes, or until the casserole is shiny on top and firm to the touch.