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Delicious Oatmeal Cream Pie Bars on a plate

Oatmeal Cream Pie Bars

These Oatmeal Cream Pie Bars are a delightful blend of soft, chewy oatmeal cookies with a creamy filling, perfect for sharing with a crowd.
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Prep Time 20 minutes
Cook Time 30 minutes
Total Time 50 minutes
Servings: 12 bars
Course: Dessert, Snack
Cuisine: American
Calories: 250
Ingredients Method Notes

Ingredients
  

For the oatmeal cookie base
  • 1 cup unsalted butter, softened 2 sticks
  • 1 cup packed brown sugar
  • 1/2 cup granulated sugar
  • 2 large eggs
  • 1 teaspoon vanilla extract
  • 1 1/2 cups all-purpose flour
  • 1 teaspoon baking soda
  • 1/2 teaspoon salt
  • 3 cups old-fashioned rolled oats
For the filling
  • 1/2 cup unsalted butter, softened 1 stick
  • 1 1/2 cups powdered sugar
  • 1 teaspoon vanilla extract
  • 3/4 cup marshmallow fluff or whipped cream cheese for a tangy version

Method
 

Preparation
  1. Preheat your oven to 350°F (175°C). Line a 9×13 inch pan with parchment paper, leaving an overhang to lift the bars later.
  2. In a large bowl, beat the butter and sugars until creamy. Add eggs and vanilla, beat until smooth.
  3. In a separate bowl, stir together flour, baking soda, and salt. Add the dry mix to the wet mix and stir until just combined. Fold in the oats.
  4. Press about half of the oat dough evenly into the prepared pan to form the base. Bake for 10 to 12 minutes, until lightly golden at the edges. Remove from oven and let cool slightly.
Filling and Assembly
  1. While the base cools, make the filling. Beat the softened butter with powdered sugar and vanilla until smooth. Fold in the marshmallow fluff until you have a smooth, spreadable cream.
  2. Spread the filling evenly over the warm base. Crumble the remaining oat dough on top and press gently so it sticks to the filling.
  3. Return the pan to the oven and bake 12 to 15 minutes, until the top is lightly golden. Cool completely in the pan, then lift out using the parchment overhang and cut into bars. Chill a bit for cleaner slices, if you like.

Notes

Press the base evenly into the pan to help the bars hold together. If the top dough is too soft to crumble, chill it for 10 minutes before topping. Let the pan cool fully before slicing, or use a warm, clean knife for neater cuts. Use old-fashioned oats for texture, quick oats make it too soft. Store bars in an airtight container, they keep well at room temperature for 2 days, or in the fridge for a week.