Oatmeal Cream Pies

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These Old Fashioned Oatmeal Cream Pies are easy to make and taste a million times better than store-bought ever could! Soft baked Oatmeal Cookies sandwiched with a simple marshmallow buttercream filling. So sweet, comforting and classically delicious. You will love these.

Move Over Little Debbie

This Oatmeal Cream Pie recipe might be my new favorite cookie! They’re so buttery, soft, sweet, delicious and all from scratch! This recipe is based off of my chewy and buttery oatmeal cookies but filled with a marshmallow buttercream filling…oh mama, they’re good! I had a really hard time not eating them all. I actually gave most of them away because they were that dangerous.

A Few Notes About Making Oatmeal Cream Pies

Lots of common pantry ingredients here! The only thing out of the ordinary, at least for my kitchen, would be the marshmallow fluff. There is no good substitute for this. You’ll have to head to the store for this, but everything else should be standard in most North American kitchens.

Cinnamon: To Add Or Not To Add

While I think it’s a 50/50 split on whether or not to add cinnamon to oatmeal cookies and therefore oatmeal cream pies, I could go either way. Please know your cookies will be delicious regardless of whether or not you add cinnamon.

While my original recipe does not include cinnamon, if you’d like to add it, simply add 1 teaspoon of ground cinnamon to your cookie dough with the rest of the dry ingredients and bake as usual.

Old Fashioned Oats vs Rolled Oats

So, rolled oats and old fashioned oats are the same thing! They are synonymous of one with another and can be used interchangeably. They are flat, round(ish) and flakey. Quick cooking oats are a slightly different beast, but can definitely be used in this recipe in place of the old fashioned/rolled oats easily 1:1. Your cookies won’t be as textural as they would be with the rolled oats, but would work well. Just be sure you’re not using steel cut oats in any cookies. You’ll likely break a tooth.

Marshmallow Buttercream Filling

So, I was new to the whole adding marshmallow fluff to your buttercream, but man oh man, I am now on board! It was so, so tasty. This recipe is essentially a Vanilla Buttercream with marshmallow fluff added in for flavor and a little extra stability. While the ingredients list is simple, be sure to read the “how to section” for this frosting. It comes together really easily, you’ll just have to add the milk in bit by bit to get the filling exactly where you want it.

How to Make Oatmeal Cream Pies

While this recipe is quite a simple one (typical creaming method for the cookies), it takes some time. So, while it’s not hard in the slightest, prepare for these to take about an hour start to finish. If you happen to have little ones at home, or if you can only bake one pan of cookies at a time, then it will take a little longer. Again, not hard, just plan accordingly. Here’s how to make these Oatmeal Cream Pies:

Prep

Preheat oven. Line two light-colored baking sheets with parchment paper and set aside.

Make the Cookie Dough

In a large bowl, cream butter and sugars together until light and fluffy, about 3-4 minutes. Stir in eggs and vanilla until well combined. Slowly incorporate the remaining ingredients until the dough has just come together.

Scoop Onto Pan, Bake + Cool

Using a medium cookie scoop, scoop into 36 cookies and place on prepared sheets. Bake 9-12 minutes or until edges are golden brown and the centers are soft but not gooey. Cool 5 minutes on the hot baking sheet before transferring to cooling racks.

How to Make Marshmallow Buttercream Filling

Combine Ingredients + Stir Until Thick and Creamy

In the bowl of a stand mixer, stir marshmallow fluff, butter, powdered sugar and vanilla together until it starts to come together. Give it some time to incorporate to a thick paste. Add milk sparingly 1 teaspoon at a time until you have a thick and creamy filling that will hold its shape. Transfer to a piping bag with a large round tip (I used the Wilton 1A).

Fill the Oatmeal Cream Pies + Serve

Match cooled cookies together with similar-sized partner cookies. Pipe about 2 tablespoons of marshmallow frosting onto the center of the bottom of a cookie. Press matching cookie onto the frosting to push filling towards the edges. Continue filling cookies until all 18 oatmeal cream pies are filled. Enjoy at room temperature.

Storing Oatmeal Cream Pies | Keeping Them Soft

Store leftover oatmeal cream pies in an airtight container at room temperature, dividing the layers with wax paper for up to 5 days.

If your cookies were baked a little crispy around the edges, add a piece of plain white sandwich bread to your airtight container, being sure the bread isn’t touching the cookies directly. I like to lay a piece of wax paper over the top of the cookies and then place the piece of bread on top, then seal with the lid. After 24 hours, the cookies should be completely soft.

Freezing Instructions

To freeze, wrap each sandwich cookie in plastic wrap then store in a freezer safe airtight container for up to 3 months! To thaw, place at room temperature until soft.

More Sandwich Cookies to Try!

• Chewy Oatmeal Cookies
• Gingerdoodle Sandwich Cookies
• Pumpkin Whoopie Pies
• Homemade Red Velvet Oreos

Definitely make these this weekend! They are so heavenly~

The printable recipe card is down below, enjoy!