Oatmeal Cream Pie Cookies
Quick oats and a little molasses give these rustic oatmeal cookies their texture and warm flavor. A thick marshmallow buttercream forms the white layer between each pair. Take the cookies out when the edges are lightly golden and the centers still look soft; they will finish setting on the baking sheet. Cool them completely before filling, then chill the sandwiches briefly so the cream holds an even band.
Ingredients for Oatmeal Cream Pie Cookies
For the cookies
- 1 cup unsalted butter, softened (225g)
- 1 cup packed light brown sugar (200g)
- 1/4 cup granulated sugar (50g)
- 1 large egg
- 1 large egg yolk
- 1 tablespoon molasses (20g)
- 1 teaspoon vanilla extract
- 1 3/4 cups all-purpose flour, spooned and leveled (210g)
- 2 cups quick oats (180g)
- 1 teaspoon baking soda
- 1 teaspoon ground cinnamon
- 1/2 teaspoon fine salt
- Optional: 1/8 teaspoon ground nutmeg
For the marshmallow filling
- 1/2 cup unsalted butter, softened (115g)
- 1 standard 7-ounce jar marshmallow fluff or marshmallow creme (200g)
- 1 cup powdered sugar (120g)
- 1/2 teaspoon vanilla extract
- Pinch of fine salt
Use quick oats for this thick dough. Old-fashioned oats have not been established as an equal swap in this formula.
Yield: About 15–16 sandwich cookies. Prep: 25 minutes. Bake: 10–12 minutes per batch, about 24–36 minutes for all batches. Total: About 1 hour 45 minutes to 2 hours, including cooling and chilling.
How to Make Oatmeal Cream Pie Cookies
- Prepare the oven and pans: Fully preheat the oven to 350°F (175°C). Line baking sheets with parchment paper.
- Combine the dry ingredients: Whisk together the flour, quick oats, baking soda, cinnamon, 1/2 teaspoon salt, and optional nutmeg.
- Make the dough: With an electric hand mixer or stand mixer, beat the 1 cup of butter with both sugars until lighter and fluffy. Beat in the egg, yolk, molasses, and 1 teaspoon vanilla. Add the dry ingredients and mix just until no flour streaks remain. The dough will be very thick.
- Scoop and bake: Portion about 2 tablespoons of dough per cookie, gently roll into balls, and place about 3 inches apart on the prepared sheets. Bake uncovered for 10–12 minutes per batch, checking at 10 minutes. Remove the cookies when the edges are lightly golden but the centers still look soft. Rotate a sheet only if your oven browns noticeably unevenly.
- Cool and pair: Leave the cookies on their sheets for about 5 minutes, then transfer to a wire rack. Let them cool completely, about 25–35 minutes total, before pairing cookies of similar size.
- Beat the filling: Beat the 1/2 cup of filling butter until smooth. Add the marshmallow fluff, powdered sugar, remaining 1/2 teaspoon vanilla, and a pinch of salt. Beat until thick and fluffy, with no butter lumps and soft ridges that hold when piped.
- Assemble: Pipe a generous tablespoon of filling onto the flat side of one cookie in each pair, stopping just inside the edge. Divide any remaining filling among the pairs. Add the second cookies flat-side down and press gently until an even white band is visible.
- Chill: Refrigerate the sandwiches for 15–20 minutes, until the filling is slightly firmer but still soft.
How to Keep the Cookies Soft
Do not wait for the tops to brown all over. The soft-looking centers will firm up during the 5-minute rest on the hot baking sheet. Scoop size and oven behavior can shift the bake time, so use the golden edges as your cue rather than the clock alone.
How to Keep the Filling in Place
Warm cookie halves can soften the butter-based filling and make it slide. Once the cookies are completely cool, match similar-sized halves and pipe the cream just inside their edges. Press only until the filling forms a visible band; pressing harder can force it down the sides.
Storing the Sandwich Cookies
Serve after the short chill. Keep filled cookies covered, and avoid tightly stacking them before the filling firms. Do not reheat the sandwiches; warmth will soften the cream.
For another warm-flavored bake, try these maple brown sugar cookies.
Nutrition
Approximate nutrition per sandwich cookie, based on 16 sandwiches: 385 calories, 4g protein, 19g fat, and 51g carbohydrates. Approximate values per 100g of finished cookies: 475 calories, 5g protein, 23g fat, and 63g carbohydrates. Values vary with cookie size, filling portions, and moisture lost during baking.
Equipment
- Electric hand mixer or stand mixer
- Baking sheets
- Parchment paper
- Wire rack
- Cookie scoop or tablespoon
- Piping bag
Ingredients
For the cookies
- 1 cup unsalted butter, softened (225 g)
- 1 cup packed light brown sugar (200 g)
- 1/4 cup granulated sugar (50 g)
- 1 large egg
- 1 large egg yolk
- 1 tablespoon molasses (20 g)
- 1 teaspoon vanilla extract
- 1 3/4 cups all-purpose flour, spooned and leveled (210 g)
- 2 cups quick oats (180 g)
- 1 teaspoon baking soda
- 1 teaspoon ground cinnamon
- 1/2 teaspoon fine salt
- Optional: 1/8 teaspoon ground nutmeg
For the marshmallow filling
- 1/2 cup unsalted butter, softened (115 g)
- 1 standard 7-ounce jar marshmallow fluff or marshmallow creme (200 g)
- 1 cup powdered sugar (120 g)
- 1/2 teaspoon vanilla extract
- Pinch of fine salt
Instructions
- Preheat the oven to 350°F (175°C). Line baking sheets with parchment paper.
- Whisk together the flour, quick oats, baking soda, cinnamon, salt, and optional nutmeg.
- Beat 1 cup butter with both sugars until lighter and fluffy. Beat in the egg, egg yolk, molasses, and 1 teaspoon vanilla.
- Add the dry ingredients and mix just until no flour streaks remain. The dough will be very thick.
- Scoop about 2 tablespoons of dough per cookie, roll gently into balls, and arrange about 3 inches apart on the prepared sheets.
- Bake for 10–12 minutes per batch, checking at 10 minutes. Remove when the edges are lightly golden and the centers still look soft. Rotate the sheet only if your oven browns unevenly.
- Let the cookies rest on the baking sheets for about 5 minutes, then transfer them to a wire rack. Cool completely, about 25–35 minutes total, and pair cookies of similar size.
- Beat the filling butter until smooth. Add the marshmallow fluff, powdered sugar, 1/2 teaspoon vanilla, and a pinch of salt. Beat until thick and fluffy, with soft ridges that hold.
- Pipe a generous tablespoon of filling onto the flat side of one cookie in each pair, stopping just inside the edge. Divide any remaining filling among the pairs.
- Top with the second cookie, flat-side down, and press gently until an even band of filling is visible.
- Refrigerate the sandwiches for 15–20 minutes, until the filling is slightly firmer but still soft.
Tips
- Use quick oats; old-fashioned oats have not been established as an equal swap for this recipe.
- Use lightly golden edges as the doneness cue rather than waiting for the cookie tops to brown.
- Let the cookies cool completely before filling so the buttercream does not soften and slide.
- Match cookies of similar size and press the tops gently to keep the filling from squeezing out.
- Chill the assembled cookies briefly to help the filling hold its shape.