Simply delicious, these oatmeal cream pie cookie bars are a real treat!
If Little Debbie snacks were a favorite of yours as a child, you’re going to love these homemade oatmeal cream pie cookie bars!
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I think most of us can remember the childhood wonder of a Little Debbie snack cake. My personal favorite was always the oatmeal cream pie (though the Fudge Round was a close second!).
Whether it’s the memory of a surprise treat in your lunchbox, or a snack eaten on the front porch on a summer afternoon, the sweet molasses flavor of the oatmeal cookies paired with the delicious marshmallow cream was pure perfection!
That treat was the inspiration behind this easy homemade dessert: oatmeal cream pie cookie bars!
Homemade Little Debbie Oatmeal Creme Pie Dessert Bars
This simple dessert starts with an oatmeal cookie base, which is soft and chewy, then is topped with a delightful marshmallow buttercream frosting.
To make these delicious cookie bars, you’ll need some molasses, because it really gives the bars that classic oatmeal cream pie flavor.
You’ll also need a jar of Marshmallow Fluff. Other than that, you probably have most of the ingredients on hand already!
How to Make Oatmeal Cream Pie Cookie Bars
You might think it’s difficult to capture the flavors of the classic snack, but it is actually really easy!
Ingredients You’ll Need:
- Brown sugar
- White sugar
- Baking powder
- Ground cinnamon
- Powdered sugar
- Marshmallow Fluff
How to Make It:
(Full printable recipe is available below)
Cream butter and sugars. First, you’ll mix together the butter and sugars until fluffy. Add some molasses, vanilla, and eggs, and keep on mixing.
Combine dry ingredients. Next, you’ll whisk together some oats, flour, baking powder, cinnamon, and salt.
Finish the batter and bake. Last, you’ll add the dry ingredients to the wet ingredients to make the batter. Spread it into a prepared pan and bake.
Make the frosting. While that’s baking, whip up a batch of the frosting by beating together butter and powdered sugar.
Add in some vanilla, heavy cream (or milk), and marshmallow fluff. Beat until it’s light and fluffy.
Frost the cookie bars. After the cookie bars are completely cool, spread the frosting on top.
Notes and Adaptations:
- At room temperature, these bars are more like a piece of cake, as they are a little softer. I prefer to eat them on a plate with a fork at this temperature.
- Once chilled in the refrigerator, they stiffen a bit into more of a bar-like consistency, which can be eaten with your hands. Both ways are super delicious–you pick! 🙂
- For the Cake Bars:
- 1 cup butter, softened
- 1 1/2 cups brown sugar, packed
- 1/2 cup white granulated sugar
- 4 Tbsp molasses
- 1 tsp vanilla extract
- 2 eggs
- 2 cups old-fashioned oats
- 1 1/2 cups all-purpose flour
- 1 tsp baking powder
- 1 1/4 tsp ground cinnamon
- 1/2 tsp salt
- For the Marshmallow Buttercream Frosting:
- 1 cup butter, softened
- 2 cups powdered sugar
- 1 tsp vanilla extract
- 7-oz Marshmallow fluff
- 1 Tbsp heavy hipping cream or milk
- Preheat oven to 350F and grease a 13x9" baking pan.
- In the bowl of a stand mixer fitted with a paddle attachment, add butter and both sugars, beating well to cream them together until fluffy.
- Add molasses and vanilla extract, beating to combine.
- Add eggs, beating well to combine.
- In a separate medium bowl, whisk together oats, flour, baking powder, cinnamon, and salt.
- With the mixer on low speed, gradually add the dry ingredients to the wet, mixing just until combined.
- Spread batter evenly into prepared pan. Bake for 35-40 minutes, until center is set.
- Remove from oven and cool completely before frosting.
- While cake bars are baking/cooling, prepare the frosting. Combine butter and powdered sugar, mixing at medium-high speed until light and fluffy.
- Add in vanilla extract and cream/milk, beating well until fluffy.
- Add in marshmallow fluff, mixing until completely combined.
- Spread evenly over cooled cake bars.
At room temperature, these bars are more like a piece of cake that you would eat with a fork. Once chilled in the refrigerator, they become more cookie bar-like and can be eaten just with your hands! Both ways are delicious--serve the way you prefer!
Amount Per Serving: Calories: 346Total Fat: 17gSaturated Fat: 10gTrans Fat: 1gUnsaturated Fat: 6gCholesterol: 59mgSodium: 216mgCarbohydrates: 47gFiber: 1gSugar: 34gProtein: 3g
Nutrition information is automatically calculated and is not guaranteed for accuracy.
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