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Oatmeal Creme Pie Cookie Bars

Oatmeal Creme Pie Cookie Bars for a Nostalgic Sweet Treat

Oatmeal Creme Pie Cookie Bars are a nostalgic twist on a classic childhood treat, featuring a chewy texture and dreamy frosting.
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Prep Time 5 minutes
Cook Time 25 minutes
Cooling Time 10 minutes
Total Time 40 minutes
Servings: 9 bars
Course: Desserts
Cuisine: American
Calories: 200
Ingredients Equipment Method Nutrition Notes

Ingredients
  

For the Cookie Bars
  • 1/2 cup Unsalted Butter Can use salted butter; omit additional salt.
  • 1 large Egg Provides structure and moisture.
  • 1 cup Light Brown Sugar Adds sweetness and molasses flavor.
  • 2 tablespoons Molasses Medium, dark, or full-bodied; maple syrup as substitute may alter flavor.
  • 1 teaspoon Vanilla Extract Adds aromatic sweetness.
  • 1/4 teaspoon Salt Can use kosher or sea salt.
  • 1 teaspoon Cinnamon Can adjust to taste or omit.
  • 1 cup Instant Oats Do not substitute with old-fashioned or whole-rolled oats.
  • 1 cup All-Purpose Flour Forms the structure of the bars.
For the Frosting
  • 1/2 cup Unsalted Butter Should be softened for easier mixing.
  • 2 cups Confectioners’ Sugar
  • 1 cup Marshmallow Creme Provides signature flavor and texture.
  • 1/4 teaspoon Salt Use sparingly to taste.

Equipment

  • 8x8 inch baking pan
  • Mixing Bowl
  • microwave
  • Whisk
  • Spatula

Method
 

Step-by-Step Instructions
  1. Preheat your oven to 350°F (175°C) and line an 8x8-inch baking pan with aluminum foil, spraying it lightly with cooking spray.
  2. Melt unsalted butter in a large bowl in the microwave for about 30-45 seconds; let it cool slightly.
  3. Whisk together the cooled melted butter and large egg, then mix in the light brown sugar, molasses, vanilla extract, salt, and cinnamon until glossy.
  4. Fold in the instant oats and all-purpose flour until just combined, which helps maintain chewy texture.
  5. Pour the batter into the prepared pan, smoothing the top and bake for 24-25 minutes, checking for doneness with a toothpick.
  6. Cool the bars in the pan for 10 minutes, then transfer to a wire rack to cool completely.
  7. Beat the softened butter and confectioners’ sugar until light and fluffy, then mix in marshmallow creme and salt until smooth.
  8. Once cooled, frost the bars with the marshmallow buttercream and slice into squares or rectangles for serving.

Nutrition

Serving: 1barCalories: 200kcalCarbohydrates: 30gProtein: 2gFat: 9gSaturated Fat: 5gPolyunsaturated Fat: 0.5gMonounsaturated Fat: 2.5gCholesterol: 30mgSodium: 150mgPotassium: 50mgFiber: 1gSugar: 15gVitamin A: 250IUCalcium: 10mgIron: 0.5mg

Notes

These bars can be stored in an airtight container for up to 5 days at room temperature or refrigerated for about a week. They can also be frozen for up to 3 months.

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