One-Bowl Oatmeal Raisin Cookie Bars
These oatmeal raisin cookie bars have all the cinnamon-spiced chew of a classic cookie, but you skip the scooping. They come together in one bowl and bake into a thick, soft tray of bars you can slice and share in about half an hour.
The edges turn golden and slightly crisp while the center stays moist and loaded with plump raisins. They are ideal for lunchboxes, bake sales, or an after-school snack that tastes like it came from a bakery.
Why These Oatmeal Raisin Bars Stay in My Rotation
I keep coming back to this recipe because it delivers that old-fashioned oatmeal cookie flavor without any fuss. The dough comes together in the same bowl you melt the butter, so cleanup is a breeze.
The bars bake up thick and chewy, with toasty oats throughout and little pockets of cinnamon-sweet raisins. They slice neatly and hold their shape, which makes them the treat that travels well and disappears fast.
Ingredients
- 1/2 cup (113g) unsalted butter, melted: let it cool slightly so you don’t cook the egg
- 3/4 cup (150g) packed light brown sugar: gives a deeper molasses note
- 1/4 cup (50g) granulated sugar: helps the edges crisp
- 1 large egg: room temperature if you remember, but cold works too
- 2 tsp vanilla extract: a good splash rounds out the warmth
- 1 cup (125g) all-purpose flour: spoon and level for the right structure
- 1/2 tsp baking soda: gives just enough lift
- 1 tsp ground cinnamon: the main spice, don’t skip it
- 1/4 tsp fine sea salt: balances the sweetness
- 2 cups (180g) old-fashioned rolled oats: use old-fashioned, not quick oats, for the chewy texture
- 1 cup (150g) raisins: plump them in hot water for 5 minutes if they seem dry
Variations / Substitutions
- Use chocolate chips: swap the raisins for an equal amount of semi-sweet chips for a classic oatmeal chocolate chip bar.
- Make them gluten-free: use a 1:1 GF baking blend and certified GF oats.
- Change the spice: add a pinch of nutmeg or allspice alongside the cinnamon.
- Dairy-free: use melted coconut oil or vegan butter in place of the butter.
If you want a full oatmeal cookie experience, my Oatmeal Cookies recipe bakes up thick and chewy too.
How to Make Oatmeal Raisin Cookie Bars
Step 1: Mix the Wet Ingredients
Heat the oven to 350°F (175°C) and line an 8×8-inch (or 9×9-inch) metal baking pan with parchment paper, leaving an overhang on two sides. In a large bowl, whisk together the melted butter, brown sugar, and granulated sugar until smooth. Add the egg and vanilla and whisk again until the mixture is glossy and well combined.
You should hear the whisk scrape the bottom a bit, no streaks of egg white. The melted butter will make the batter soft and easy to stir, so no mixer needed.
Step 2: Stir in the Dry Ingredients
Sprinkle the flour, baking soda, cinnamon, and salt directly over the wet mixture. Use a rubber spatula or wooden spoon to stir until just combined and no dry pockets remain. The dough will look a little shaggy, but that’s fine.
Stop mixing when you see no more streaks of flour. Overworking at this stage can make the bars tough.
Step 3: Fold in the Oats and Raisins
Add the oats and raisins to the bowl. Fold them in with your spatula until they’re evenly distributed. The dough will be thick and a bit sticky, but the oats should be fully coated.
If you plumped the raisins, make sure to drain them well and pat them dry first, extra moisture can throw off the bake.
Step 4: Press and Bake
Scrape the dough into your prepared pan and use damp fingertips or the back of a spoon to press it into an even layer, pushing it all the way to the corners. Bake on the middle rack for 22 to 28 minutes, until the top is golden brown and the bars are set at the center.
You’ll know they’re done when the edges have pulled away slightly from the sides and a toothpick inserted in the middle comes out with a few moist crumbs. The bars will firm up as they cool.
Step 5: Cool and Slice the Bars
Set the pan on a wire rack and let the bars cool completely in the pan. This takes about 1 hour, but it’s worth the wait, warm bars are way too fragile to cut.
Use the parchment overhang to lift the solid block out of the pan. Transfer it to a cutting board and slice into 12 to 16 squares with a sharp chef’s knife. Serve at room temperature with a cold glass of milk.
Tips for the Chewiest Bars
- Use old-fashioned rolled oats: quick oats turn mushy here, so stick with the thick flakes.
- Don’t skip the parchment sling, it makes getting the bars out of the pan simple and prevents sticking.
- For neat, clean slices, chill the cooled block for 10 minutes in the fridge before cutting.
- If your bars seem pale after 25 minutes, leave them in a couple more minutes until the top is golden, underbaked bars can be gummy.
Bake times shift a bit with pan size and material:
| Pan | Approximate Bake Time |
|---|---|
| 8×8-inch metal | 25 to 28 minutes |
| 9×9-inch metal | 22 to 25 minutes |
| 8×8-inch glass | add 3 to 5 minutes |
Keeping the Bars Fresh
Store cut bars in an airtight container at room temperature for up to 4 days. To keep them soft, slip a slice of plain sandwich bread into the container, it releases moisture and prevents drying out. You can also freeze them for up to 3 months; thaw at room temperature.
Frequently Asked Questions
Can I use quick oats instead of old-fashioned?
No, quick oats will break down and make the bars gummy. Old-fashioned rolled oats give the right chewy texture.
Can I make these vegan?
Yes, use melted coconut oil instead of butter and a flax egg (1 tbsp ground flax + 3 tbsp water). The bars will be a little softer, but still have plenty of cinnamon flavor.
Can I freeze the unbaked dough?
Yes, press the dough into the pan, wrap it well, and freeze for up to 2 months. Bake straight from the freezer, adding about 5 extra minutes to the time.
What if I don’t have brown sugar?
You can use all granulated sugar, but the bars will lose the chewy molasses character and turn out crisper. You can stir 1 teaspoon of molasses into the wet mix to get some of that back.
Oatmeal Raisin Cookie Bars Recipe
Ingredients
Method
- Heat oven to 350°F (175°C). Line an 8×8-inch metal pan with parchment. In a large bowl, whisk together melted butter, brown sugar, and granulated sugar. Add egg and vanilla, whisk until glossy.
- Sprinkle flour, baking soda, cinnamon, and salt over the wet mixture. Stir with a spatula just until combined, a little shaggy is fine.
- Fold in the oats and raisins until evenly distributed and the oats are coated.
- Press the dough into the prepared pan in an even layer. Bake 22 to 28 minutes, until golden and set in the center (a toothpick should have moist crumbs).
- Cool completely in the pan on a wire rack, about 1 hour. Lift out with the parchment, slice into squares, and serve.
