Introduction

This Oatmeal Cream Pie Cake is a delightful twist on the classic cookie, transforming it into a layered cake filled with creamy vanilla frosting and topped with a smooth white chocolate glaze. Its comforting cinnamon and oat flavors make it a cozy dessert perfect for any occasion.

A slice of three-layer light brown cake with white creamy frosting between each layer and covering the outside sits on a white plate with a ridged edge. The cake texture looks soft and crumbly. A silver fork rests on the plate, holding a bite-sized piece of the cake with frosting. Around the plate on a white marbled surface, there are cookie crumbs scattered and two whole sandwich cookies are placed near the top left corner. Another white plate with a partially visible slice of the same cake is at the bottom left corner. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

2 1/2 cups water
2 cups quick cook oats (uncooked)
2 2/3 cups all purpose flour (*see notes below for measuring*)
1 tbsp + 1 tsp ground cinnamon
1 teaspoon fine sea salt
1/2 tsp nutmeg
2 teaspoons baking soda
1 cup unsalted butter (room temperature)
1 cup Domino® Granulated Sugar
1 cup Domino® Light Brown Sugar (packed)
1 tbsp vanilla extract
3 large eggs (room temperature)
1/4 cup full-fat sour cream (room temperature)
2 1/2 cups unsalted butter (room temperature)
4 cups powdered sugar
2 tbsp heavy cream
2 tsp vanilla extract
1 tsp vanilla bean paste
1 cup white chocolate chips
1/4 cup + 3 tbsp heavy cream
White food coloring (optional but makes the glaze more white instead of yellow)
Oatmeal cream pie cookies (for decorating)

Instructions

Step 1: Preheat the oven to 350°F (180°C). Line three 8-inch cake pans with parchment paper on the bottoms and set them aside.
Step 2: Bring a pot of water to a boil. Add the oats, stir, then remove the pot from heat. Cover and let it sit for 20 minutes. Allow the oatmeal to cool to room temperature before using.
Step 3: In a bowl, whisk together the flour, baking soda, salt, cinnamon, and nutmeg. Set aside.
Step 4: In a stand mixer, beat the butter and both sugars on medium speed for 5 minutes until light and fluffy. Add vanilla, eggs, and sour cream, mixing until combined. Scrape the sides as needed.
Step 5: Mix in the cooled oats until just combined. Then fold in the flour mixture, mixing gently until combined. The batter will be very thick.
Step 6: Divide the batter evenly into the prepared pans (about 600g each). Bake for 20–22 minutes, until a toothpick inserted comes out with a few moist crumbs. Cool in pans on a wire rack, then run a spatula around edges and invert to remove cakes.
Step 7: To make the buttercream, beat the butter in a mixing bowl on medium speed until light and fluffy. Gradually add powdered sugar on low speed. Increase to medium and beat for 3–5 minutes until fluffy. Mix in heavy cream, vanilla extract, and vanilla bean paste.
Step 8: Assemble the cake by placing one oatmeal cake layer on a stand. Spread 1 cup of vanilla frosting on top. Add the next layer and repeat, finishing with the final layer upside down for a flat surface.
Step 9: Spread the remaining frosting evenly over the sides and top of the cake in a thin layer. Set aside while preparing the glaze.
Step 10: Heat the 1/4 cup + 3 tbsp heavy cream until warm. Pour over white chocolate chips and stir until melted and smooth. Add white food coloring if desired. Let the glaze cool slightly to avoid melting the frosting, then pour over the cake on a wire rack with a tray underneath, spreading to edges so it drips down the sides.
Step 11: Allow the glaze to set. Decorate the top with crumbled oatmeal cream pie cookies and pieces for a beautiful finish.

Tips & Variations

For measuring flour accurately, spoon it into your cup and level with a knife instead of scooping directly from the bag to avoid dense cake layers.
Use room temperature ingredients for better mixing and a smoother batter.
If you prefer a more intense cinnamon flavor, sprinkle a little extra cinnamon into the frosting.
Substitute the oatmeal cream pie cookies for your favorite cookie crumbs to change up the decoration.
The white food coloring is optional but helps the glaze stay a bright white rather than yellowish.

Storage

Store the cake covered in the refrigerator for up to 4 days. To serve, bring to room temperature for about 30 minutes. Leftover cake can be wrapped tightly and frozen for up to 2 months; thaw overnight in the refrigerator before enjoying.

How to Serve

The image shows a three-layer cake with light brown textured cake layers and two thick white creamy frosting layers between them. The outside of the cake is covered in smooth white frosting, and the top is decorated with broken pieces of small brown cookies placed unevenly. The cake sits on a brown plate with some crumbs around it, and the background is a white marbled texture. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use old-fashioned oats instead of quick cook oats?

Quick cook oats are preferred for a softer texture in the cake. If using old-fashioned oats, pulse them briefly in a food processor to break them down slightly before cooking and adding to the batter.

Why is the cake batter so thick?

The combination of oats and thick flour mixture creates a dense batter, which is normal for this recipe. This texture helps produce a moist cake with the right chewiness reminiscent of oatmeal cream pies.