A cozy, meal-prep-friendly breakfast that tastes like an oatmeal cookie—without the fuss.

There’s a moment every autumn when the air turns crisp, the light slants just right through the kitchen window, and I suddenly crave something warm and nostalgic—something that smells like cinnamon and feels like a hug. That’s when I pull out my trusty 9-inch square pan and whip up this Simple Baked Oatmeal with Raisins and Cinnamon. My kids call it “oatmeal cake,” and honestly, I can’t argue. The edges caramelize slightly, the raisins plump into jammy pockets of sweetness, and the center stays custardy and tender. It’s the kind of recipe that makes you look like a kitchen hero even though you spent five minutes stirring things together in one bowl.

I started making this version years ago when I was pregnant with my second child and morning sickness made every breakfast food unappealing—except oatmeal cookies. I figured if I could turn those flavors into a legitimate breakfast, everyone wins. Fifteen minutes of passive oven time later, I had a pan of golden, cinnamon-scented squares that could be portioned, wrapped, and reheated on the busiest of mornings. Fast-forward to today: this baked oatmeal is still on weekly rotation. It’s my secret weapon for house-guest mornings, pot-luck brunches, and those Sundays when I want the house to smell like I’ve got my life together.

Why This Recipe Works

One-bowl batter: Whisk, pour, bake—no electric mixer or fancy gear required.
Pantry staples: Old-fashioned oats, raisins, cinnamon, and a handful of fridge basics.
Meal-prep champion: Bake once, portion into nine squares, and breakfast is done for the week.
Customizable: Swap raisins for berries, add nuts, or make it dairy-free with ease.
Texture magic: Soft custardy center with slightly chewy edges—like bread pudding meets granola bar.
Kid-approved: Serve warm with a drizzle of maple syrup; watch even picky eaters devour their oats.

Ingredients You'll Need

Great baked oatmeal starts with humble ingredients, but a few choices can elevate the final dish from “pretty good” to “can-I-have-seconds?”

Old-fashioned rolled oats: They retain their chewy integrity and create that signature custardy texture. Quick oats will turn mushy, and steel-cut will stay too firm—stick with old-fashioned. Buy them in the bulk bins if you can; freshness equals better flavor.

Ground cinnamon: The star spice. I use a generous two teaspoons of fresh Vietnamese cinnamon for warmth and complexity. If your jar has been sitting in the cupboard since last winter, treat yourself to a new one—aroma equals potency.

Raisins: Opt for plump, unsweetened Thompson or golden raisins. If they’re a bit dry, soak them in hot water for five minutes and blot dry; they’ll bake up juicy rather than shriveled. Prefer chocolate chips or blueberries? See the variations section.

Milk: Whole milk yields the creamiest custard, but 2 %, almond, oat, or soy all work. If using plant milk, choose an unsweetened variety so you control the sugar.

Eggs: Two large eggs bind everything together and create that pudding-like center. For an egg-free version, substitute 2 tablespoons ground flaxseed whisked with 5 tablespoons water; let stand 5 minutes to thicken.

Pure maple syrup: Just half a cup is enough to sweeten the entire pan while adding a caramel undertone. Honey or agave are fine swaps; brown sugar works too—just whisk it in with the dry ingredients.

Melted butter: Adds richness and helps the edges crisp. Coconut oil is a delicious dairy-free alternative; use refined if you don’t want coconut flavor competing with cinnamon.

Baking powder & salt: The former lifts the custard slightly; the latter amplifies every other flavor. Don’t skip the salt—just ½ teaspoon makes a difference.

Vanilla extract: A splash rounds out the sweetness and marries the flavors. Choose pure, not imitation, for the best aroma.

How to Make Simple Baked Oatmeal with Raisins and Cinnamon

Preheat & prep

Position a rack in the center of your oven and preheat to 375 °F (190 °C). Lightly coat a 9-inch square baking pan with non-stick spray or a thin slick of butter. Line the bottom with a strip of parchment if you’d like effortless removal for neat squares.

Combine dry ingredients

In a large mixing bowl, whisk together 2 cups (180 g) old-fashioned oats, 2 teaspoons ground cinnamon, 1 teaspoon baking powder, and ½ teaspoon kosher salt. Distributing the leavening now prevents bitter pockets later.

Whisk wet ingredients

In a separate medium bowl, beat 2 large eggs until the yolks and whites are fully combined and slightly frothy. Whisk in 1 ¾ cups (420 ml) milk, ½ cup (120 ml) pure maple syrup, ¼ cup (60 g) melted butter (cooled slightly), and 2 teaspoons vanilla extract until everything is silky smooth.

Fold everything together

Pour the wet mixture over the oat mixture and stir with a rubber spatula just until no dry streaks remain. Gently fold in ⅔ cup (100 g) raisins so they’re evenly dispersed. Let the batter stand for 5 minutes; this brief rest hydrates the oats and produces a creamier interior.

Transfer & level

Pour the mixture into your prepared pan and jiggle it gently so the top is even. If some raisins are poking up, push them just below the surface to prevent burning.

Bake to golden perfection

Bake for 28–32 minutes, until the center is just set and the edges pull slightly from the sides. A toothpick inserted in the middle should come out with a few moist crumbs, not wet batter. The oatmeal will continue to firm as it cools.

Cool & slice

Place the pan on a wire rack and cool for 10 minutes. This short rest lets the custard set, preventing a sloppy first cut. Slice into 9 generous squares or 12 smaller rectangles. Serve warm with an extra drizzle of maple or a spoonful of yogurt.

Store for the week

Leftovers keep refrigerated in an airtight container for up to 5 days. Reheat in the microwave for 30–40 seconds or in a 325 °F oven for 8 minutes. See freezing instructions below.

Expert Tips

Plump your raisins

Soak raisins in hot water for 5 minutes, then blot dry. They’ll bake up juicy and prevent burnt bits.

Don’t overbake

The center should jiggle slightly when you shake the pan; it sets as it cools. Overbaking yields dry squares.

Double the batch

Bake in a 9×13 pan for 35–38 minutes. You’ll have 18 squares—perfect for two busy weeks or sharing with neighbors.

Overnight option

Assemble the night before, cover, and refrigerate. Bake straight from cold, adding 3 extra minutes.

Crisp edges hack

Dust the top with 1 tablespoon granulated sugar before baking for a delicate, brûléed crunch.

Protein boost

Replace ½ cup milk with vanilla protein shake or Greek yogurt for an extra 6 g protein per square.

Variations to Try

Apple-Cinnamon: Fold in 1 cup diced peeled apple and a pinch of nutmeg. Drizzle with caramel sauce to serve.
Banana Bread: Swap maple syrup for 2 mashed ripe bananas and reduce milk to 1 ½ cups. Add walnuts.
Berry Almond: Replace raisins with 1 cup fresh or frozen blueberries and sprinkle the top with sliced almonds.
Carrot Cake: Add 1 cup finely grated carrot, ¼ cup unsweetened coconut, and ½ teaspoon ginger. Top with cream-cheese glaze.
Peanut Butter-Chocolate: Swirl ⅓ cup peanut butter into the batter and sub mini chocolate chips for raisins.

Storage Tips

Refrigerator: Cool squares completely, transfer to an airtight container, and refrigerate up to 5 days. Place parchment between layers to prevent sticking.

Freezer: Wrap individual squares in plastic wrap, then foil, and freeze up to 3 months. Thaw overnight in the fridge or microwave directly from frozen for 60–90 seconds.

Reheat: Oven method—place squares on a lined sheet, cover loosely with foil, and warm at 325 °F for 8–10 minutes. Microwave method—heat on a microwave-safe plate for 30–40 seconds; drizzle with milk to restore moisture.

Make-ahead batter: Whisk everything, cover tightly, and refrigerate up to 24 hours. When ready to bake, preheat oven, pour into prepared pan, and add 3 extra minutes to bake time.

Frequently Asked Questions

Quick oats will work but yield a softer, almost mushy texture. If that’s all you have, reduce milk by ¼ cup and bake 2 minutes less.

Use flax eggs (2 Tbsp ground flax + 5 Tbsp water), plant milk, and coconut oil instead of butter. Maple syrup is already vegan-friendly.

Absolutely—halve all ingredients and bake in an 8-inch square pan for 22–25 minutes. Check doneness with a toothpick.

Overbaking is the usual culprit. Next time, pull it when the center still jiggles slightly; it firms as it cools. You can also stir 2 Tbsp additional milk into leftovers before reheating.

Yes—substitute up to ½ cup milk with vanilla protein shake or add ¼ cup plain protein powder. Increase milk by 2 Tbsp to balance dryness.

Oats are naturally gluten-free but often processed in facilities that handle wheat. Use certified gluten-free oats and you’re good to go.