Quick Recipe Version (TL;DR)
Quick Ingredients
- 2 1/2 cups (225 g) old-fashioned rolled oats
- 2 tsp baking powder
- 1 tsp ground cinnamon
- 1/2 tsp fine salt
- 1/2 cup (100 g) packed light brown sugar
- 2 large eggs
- 2 cups (480 ml) whole milk (or 2%)
- 1/4 cup (60 g) unsalted butter, melted (plus more for the pan)
- 2 tsp vanilla extract
- Cinnamon swirl: 3 tbsp (42 g) unsalted butter, melted + 1/3 cup (67 g) packed light brown sugar + 1 1/2 tsp ground cinnamon
- Cream cheese drizzle: 4 oz (113 g) cream cheese, softened + 1/2 cup (60 g) powdered sugar + 1/2 tsp vanilla + 2–4 tbsp (30–60 ml) milk + pinch of salt
Do This
- 1) Heat oven to 350°F (175°C). Butter an 8-inch (20 cm) square baking dish.
- 2) Mix oats, baking powder, cinnamon, salt, and brown sugar in a bowl.
- 3) Whisk eggs, milk, melted butter, and vanilla; stir into oat mixture and pour into dish.
- 4) Stir together swirl ingredients; spoon over top and drag a knife through to marble.
- 5) Bake 35 minutes, until edges are set and center is just barely firm.
- 6) Cool 10 minutes. Whisk drizzle until smooth and pourable.
- 7) Cut into 9 squares and drizzle generously. Serve warm.
Why You’ll Love This Recipe
- Cinnamon-roll vibes, zero yeast: You get that warm cinnamon-brown-sugar flavor without kneading, rising, or rolling dough.
- Dessert-for-breakfast energy: Cozy, sweet, and satisfying, but still made from hearty oats.
- Meal-prep friendly: Bakes as a slab, cuts into squares, and reheats beautifully all week.
- That tangy drizzle: The cream-cheese-style topping balances the sweetness and makes it feel truly “cinnamon roll.”
Grocery List
- Produce: Lemon (optional, for a brighter drizzle)
- Dairy: Milk, unsalted butter, cream cheese, eggs
- Pantry: Old-fashioned rolled oats, light brown sugar, powdered sugar, vanilla extract, ground cinnamon, baking powder, fine salt
Full Ingredients
Baked Oatmeal Base
- Unsalted butter, for greasing the pan
- 2 1/2 cups (225 g) old-fashioned rolled oats
- 2 tsp baking powder
- 1 tsp ground cinnamon
- 1/2 tsp fine salt
- 1/2 cup (100 g) packed light brown sugar
- 2 large eggs
- 2 cups (480 ml) whole milk (or 2%)
- 1/4 cup (60 g) unsalted butter, melted and slightly cooled
- 2 tsp vanilla extract
Cinnamon Roll-Style Swirl
- 3 tbsp (42 g) unsalted butter, melted
- 1/3 cup (67 g) packed light brown sugar
- 1 1/2 tsp ground cinnamon
- Pinch of fine salt
Cream Cheese Drizzle
- 4 oz (113 g) cream cheese, softened to room temperature
- 1/2 cup (60 g) powdered sugar, sifted if lumpy
- 1/2 tsp vanilla extract
- Pinch of fine salt
- 2–4 tbsp (30–60 ml) milk, as needed for consistency
- Optional: 1 tsp fresh lemon juice (5 ml), for a tangier, brighter drizzle
Step-by-Step Instructions
Step 1: Prep the oven and pan
Preheat your oven to 350°F (175°C). Generously butter an 8-inch (20 cm) square baking dish (glass or ceramic both work well). Set it aside.
Step 2: Mix the dry ingredients
In a large bowl, stir together the rolled oats, baking powder, cinnamon, salt, and brown sugar. Break up any brown sugar clumps so the sweetness is evenly distributed.
Step 3: Mix the wet ingredients and combine
In a medium bowl (or a large measuring jug), whisk the eggs until smooth. Whisk in the milk, melted butter, and vanilla.
Pour the wet mixture into the dry oat mixture and stir until everything is evenly moistened. Let the mixture sit for 5 minutes so the oats can begin absorbing the liquid (this helps the baked oatmeal slice neatly).
Step 4: Assemble the oatmeal in the pan
Pour the oat mixture into the prepared baking dish. Use a spatula to spread it into an even layer, nudging oats into the corners so it bakes uniformly.
Step 5: Make and add the cinnamon swirl
In a small bowl, stir together the melted butter, brown sugar, cinnamon, and a pinch of salt. Spoon the mixture over the top of the oatmeal in small puddles.
Use a butter knife to gently swirl the cinnamon mixture through the top layer (think marbling). Don’t overmix—you want distinct cinnamon ribbons.
Step 6: Bake until set and cinnamon-fragrant
Bake for 35 minutes, or until the edges are set and lightly golden and the center feels mostly firm (it should not look wet or sloshy). A toothpick inserted near the center should come out with moist crumbs, not raw liquid.
Let cool in the pan for 10 minutes. This resting time helps the squares hold their shape when sliced.
Step 7: Whisk the cream cheese drizzle and finish
In a medium bowl, whisk the softened cream cheese until smooth. Whisk in the powdered sugar, vanilla, and salt.
Whisk in milk, 1 tablespoon at a time, until you reach a thick-but-pourable consistency. If using, whisk in the lemon juice for extra tang.
Cut the baked oatmeal into 9 squares and drizzle over the warm (or room-temperature) squares. For maximum cinnamon-roll vibes, serve slightly warm so the drizzle melts into the swirls.
Pro Tips
- Use rolled oats, not steel-cut: Old-fashioned rolled oats give the right tender-but-sliceable texture. Steel-cut oats won’t cook through in the same time.
- Let the mixture rest before baking: That quick 5-minute soak helps the oats hydrate so the bake sets up like a soft bar instead of a loose casserole.
- Don’t overbake: Pull it when the center is just set. Overbaking makes baked oatmeal dry, and it won’t feel “cinnamon roll” soft.
- Room-temp cream cheese matters: Softened cream cheese whisks smooth; cold cream cheese leads to lumps.
- Adjust drizzle thickness on purpose: Use 2 tbsp milk for a thicker frosting-like drizzle, 4 tbsp for a thinner glaze that spreads easily.
Variations
- Maple-pecan cinnamon roll baked oatmeal: Add 1/2 cup (55 g) chopped pecans to the batter and replace 1 tbsp (12 g) of the brown sugar with 1 tbsp (15 ml) maple syrup.
- Extra “sticky-bun” topping: Before baking, sprinkle 2 tbsp (25 g) brown sugar over the swirls for a more caramelized top.
- Dairy-free option: Use unsweetened oat milk and replace butter with melted refined coconut oil (same amounts). For the drizzle, use a dairy-free cream cheese alternative and adjust milk as needed.
Storage & Make-Ahead
Store leftover squares in an airtight container in the refrigerator for up to 5 days. For best texture, store the drizzle separately and add after reheating.
To reheat, warm individual squares in the microwave for 25–40 seconds (from chilled), or cover and warm in a 300°F (150°C) oven for 10–12 minutes.
To freeze, wrap squares tightly and freeze for up to 2 months. Thaw overnight in the fridge, then reheat as above. The cream cheese drizzle is best made fresh, but you can mix it up to 3 days ahead and refrigerate; thin with a splash of milk before serving.
Nutrition (per serving)
Approximate, based on 1 of 9 squares: 290 calories, 36 g carbs, 8 g protein, 13 g fat, 3 g fiber, 17 g sugar, 260 mg sodium.
